a cell phone plan costs $28.90 per month for 400 minutes of talk time. it costs an additional $0.07 per minute for each minute over 400 minutes. to get e-mail access, it costs 10% of the price for 400 minutes of talk time. your bill, which includes e-mail, is the same each month for 8 months. the total cost for all months is $298.56. write and solve an equation to find the number of minutes of talk time you use each month.

(a)  The synchronous reactance of the alternator is 0.001953125 Ω.

The synchronous reactance [tex]X_{s}[/tex] of the alternator can be calculated using the formula:

[tex]X_{s} = (Vt^2) / (3 * VL * S_{base})[/tex]

where [tex]V_{t}[/tex] is the rated line-to-line voltage of the alternator, VL is the rated line-to-neutral voltage of the alternator (which is the same as the rated voltage for a Y-connected alternator), and S_base is the apparent power rating of the alternator (which is equal to the rated power factor of the alternator times the rated apparent power). Substituting the given values, we get:

[tex]X_{s} = (13.5^2) / (3 * 13.5 * 1600) = 0.001953125[/tex] Ω

Therefore, the synchronous reactance of the alternator is 0.001953125 Ω.

(b) The percentage voltage regulation at full-load 0.8 power factor leading is 23.15%.

The percentage voltage regulation (%VR) at full-load 0.8 power factor leading can be calculated using the formula:

%VR = (E - Vl) / Vl * 100%

where E is the generated voltage of the alternator, and Vl is the terminal voltage of the alternator at full-load 0.8 power factor leading. We can assume that the armature resistance and inductance are negligible compared to Xs for this calculation. Using the given values, we first calculate the apparent power S of the load:

S = P / pf = 1280 / 0.8 = 1600 kVA

Since the load is at unity power factor, the current drawn from the alternator is also 1600 A. Therefore, the voltage drop across Xs is:

Vx = Xs * I = 0.001953125 * 1600 = 3.125 V

The generated voltage E is equal to the terminal voltage Vl plus the voltage drop across Xs:

E = Vl + Vx

The percentage voltage regulation is then:

%VR = (E - Vl) / Vl * 100% = (Vl + Vx - Vl) / Vl * 100% = Vx / Vl * 100%

Substituting the given values, we get:

%VR = 3.125 / 13.5 * 100% = 23.15%

Therefore, the percentage voltage regulation at full-load 0.8 power factor leading is 23.15%.

(c) If the %VR value is taken at half-load lagging power factor, it will be higher than the %VR value at full-load 0.8 power factor leading. This is because the load impedance at half-load lagging power factor has a lower magnitude than the load impedance at full-load 0.8 power factor leading, which means that the voltage drop across [tex]X_{s}[/tex] will be a larger fraction of the terminal voltage, resulting in a larger %VR value.

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Answer:

√89

Step-by-step explanation:

√(4+4)2+(0-5)2

√(8)2+(-5)2

√64+25

√89

The degree form for 3π/4 radians is 135°.The degree form for 3π/4 radians is 135°. To convert radians to degrees, we multiply the radian measure by the conversion factor of 180°/π.

In this case, we have (3π/4) * (180°/π) = (3 * 180°) / 4 = 540° / 4 = 135°. Therefore, 3π/4 radians is equivalent to 135° in the degree form.

To convert an angle from radians to degrees, we use the conversion factor of 180°/π. This conversion factor represents the relationship between a full circle (360°) and 2π radians.

In this case, we want to convert the angle 3π/4 radians to degrees. We multiply the radian measure (3π/4) by the conversion factor (180°/π):

(3π/4) * (180°/π) = (3 * 180°) / 4 = 540° / 4 = 135°

By canceling out the common factor of π and simplifying the expression, we find that 3π/4 radians is equal to 135°.

Therefore, the degree form of the angle 3π/4 radians is 135°.

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a) The 7th percentile of the bill amounts is given as follows: $80.64.

b) The 62nd percentile of the bill amounts is given as follows: $116.24.

c) The median of the bill amounts is given as follows: $110.14.

We first must use the z-score formula, as follows:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

In which:

The z-score represents how many standard deviations the measure X is above or below the mean of the distribution, and can be positive(above the mean) or negative(below the mean).

The z-score table is used to obtain the p-value of the z-score, and it represents the percentile of the measure represented by X in the distribution.

The mean and the standard deviation for this problem are given as follows:

[tex]\mu = 110.14, \sigma = 20[/tex]

The median is the same as the mean, hence it is given as follows:

$110.14.

The 7th percentile is X when Z = -1.475, hence:

-1.475 = (X - 110.14)/20

X - 110.14 = -1.475 x 20

X = $80.64.

The 62nd percentile is X when Z = 0.305, hence:

0.305 = (X - 110.14)/20

X - 110.14 = 0.305 x 20

X = $116.24.

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Answer:

The solution is x = + 0.77 , -0.77

Step-by-step explanation:

The equation is

[tex]x^3 - 3x^2 - 4 = \frac{1}{x} -1 +5\\x^4 -3x^3 -4x = 1-4x\\x^4 - 3x^3 = 1\\x^3 (x-3) = 1\\\\x^4 -3x^3 -1 = 0\\x^4 -3x^3 -1[/tex]

The solutions to the equation is

x = + 0.77 , -0.77

Answer:

0.91 and 3.69

Step-by-step explanation:

Answer:

Step-by-step explanation:

3:2 = 2.5:1.5

half of 2 is 1 so if you had 1.5 it would only be half. For a better explanation, 1 minute is 60 seconds half of a minute is 30 seconds. if you have 45 seconds it would be 3/4 of a second. this is hard for me to explain so if you need more examples just tell me in the comments.

i hope this helps

have a nice day/night

mark brainliest please:)

Therefore, the decimal representations of irrational numbers satisfy conditions 1 and 2; that is, irrational numbers are decimals that do not terminate and do not repeat. Knowing these properties, it is now possible for us to construct irrational numbers in decimal form at will.

for spanish people

Por lo tanto, las representaciones decimales de números irracionales cumplen las condiciones 1 y 2; es decir, los números irracionales son decimales que no terminan y no se repiten. Conociendo estas propiedades, ahora es posible para nosotros construir números irracionales en forma decimal a voluntad.

Answer:

$33,040

Step-by-step explanation:

Hope this helps and have a wonderful day!!!

Answer:

$30520

Step-by-step explanation:

Answer:

295

Step-by-step explanation:

Answer:

295!

Step-by-step explanation:

72 - 12 = 60

48 x 60 = 2880

2880 - 225 = 2655

2655 / 9 = 295

Have you ever heard of PEMDAS? It is the order in which to solve equations like this one. Here's what it stands for:

Parenthesis

Exponents

Multiplication

Division

Addition

Subtraction

I hope this is helpful for future math equations similar to this one.

Answer:

4 - 12x

Step-by-step explanation:

Use the distributive property.

-6(-2/3 +2x) =

= -6 × -2/3 + (-6) × 2x

= 4 - 12x

The 99% confidence interval for the true proportion of undergraduate college students with home internet access is: 0.872 ± 0.057 or (0.815, 0.929).

To estimate the true proportion of undergraduate college students (18-23 years) with home internet access, we can use a confidence interval.

The point estimate for the proportion is 157/180 = 0.872. To find the margin of error, we can use the formula:

Margin of error = z* (sqrt(p_hat*(1-p_hat)/n))

where z* is the critical value for the desired confidence level, p_hat is the sample proportion, and n is the sample size.

For a 99% confidence level, the critical value is 2.576. Plugging in the values, we get:

Margin of error = 2.576 * (sqrt(0.872*(1-0.872)/180)) = 0.057

Therefore, the 99% confidence interval for the true proportion of undergraduate college students with home internet access is:

0.872 ± 0.057 or (0.815, 0.929)

This means that we are 99% confident that the true proportion of undergraduate college students with home internet access falls between 0.815 and 0.929.

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Answer:

x = 49.5°

Step-by-step explanation:

∠ABC = 90°

∠CBD = 45%∠ABC

∠CBD = 0.45(90)

∠CBD = 40.5°

x = ∠ABC - ∠CBD

x = 90 - 40.5

x = 49.5°

Answer: 1.2 blocks

Step-by-step explanation:

Timothy walks 12 blocks in 10 minutes so it can be written as

12 blocks = 10 minutes

divide both sides by 10

1.2 blocks per minute

Answer:10

Step-by-step explanation:believe me bro

To the nearest minute, it will be 10 minutes until there are 70 grams of the element remaining.

The time the element took to decay can be found by using the following formula:

[tex]F=P(1-r)^{t}[/tex]

Where:

We can find the answer by substituting the values.

[tex]F=P(1-r)^{t}\\\Rightarrow 70=840(1-0.229)^{t}\\\Rightarrow \frac{70}{840} =(1-0.229)^{t}\\0.0833=(1-0.229)^{t}\\t=9.56\\\approx10 \text{ minutes}[/tex]

Therefore, we have found that the element will take around 10 minutes to have 70 grams remaining.

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answer in the picture

Answer:

The illustration below shows the graph of yyy as a function of xxx.

Complete the following sentences based on the graph.

Initially, as xxx increases, yyy

Step-by-step explanation:

Answer:

(x+1)^2 + y ^2 = 16

Step-by-step explanation:

center: (-1,0)

radius=4

(x-h)^2 + (y-k)^2 = r^2

(h,k) = center

plug in the center

(x+1)^2 + (y+0) ^2 = r^2

r^2 = (4)^2

r^2=16

(x+1)^2 + y^2 = 16

Answer:

m = 4.7

Step-by-step explanation:

If you plug in these values in the slope formula, this is what happens:)

Answer:

47/10x

**Do not leave your answer as a decimal, slope is usually in fraction form**

Step-by-step explanation:

Slope Formula: [tex]\frac{\text{rise}}{\text{run}} / \frac{y_2 - y_1}{x_2 - x_1}[/tex] In this formula, subtract the 1st coordinate from the second. So, the 2nd y coordinate goes first, place a "minus" sign, and then the 2nd y-coordinate. This is the same for the x coordinates.

Finding the Answer: To find the answer, we just plug the numbers correctly into the equation, just as I explained above. We would do 55-8 first, which is 47, and then 12-2 which is 10.

Combined, the answer is 47/10x. You always place an x after the slope, which can be used to plug in other numbers. The answer cannot be simplified anymore, so this is simplfied.  

Answer:

transpose -4 to left

and 5 to left

subtract and and after transpose you will have a sign change

then you can divide

12/4,18/9

so,

x<2,x>3

9514 1404 393

Answer:

Step-by-step explanation:

See the attached.

Janice needs to be willing to ask at least 16 boys to have a 99.7% chance of getting a "yes" and going to the Sadie Hawkins dance.

To determine how many boys Janice needs to be willing to ask in order to have a 99.7% chance of getting a "yes" and going to the Sadie Hawkins dance, we can use the concept of probability and the binomial distribution.

The probability of a random boy saying yes is 45%, which means the probability of a boy saying no is 55%. Let's assume Janice asks "n" boys.

The probability of at least one boy saying yes can be calculated using the complement rule. The complement of the event "at least one boy saying yes" is the event "all boys saying no."

The probability of all "n" boys saying no is (0.55)^n, as the probability of each boy saying no is 55%.

To find the number of boys Janice needs to ask to have a 99.7% chance of going, we want the complement probability (all boys saying no) to be 0.003. Therefore:

(0.55)^n ≤ 0.003

Taking the logarithm of both sides:

n * log(0.55) ≤ log(0.003)

Solving for "n":

n ≥ log(0.003) / log(0.55)

Using a calculator:

n ≥ 15.154

Since Janice can't ask a fraction of a boy, we need to round up the value of "n" to the nearest whole number.

Therefore, Janice needs to be willing to ask at least 16 boys to have a 99.7% chance of getting a "yes" and going to the Sadie Hawkins dance.

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Solving a set of linear inequalities in several variables is an NP-hard problem, meaning there is no known polynomial-time algorithm to find a satisfying assignment.

Unlike linear equalities, solving a set of linear inequalities in several variables is an NP-hard problem. This means that there is no known polynomial-time algorithm to find a satisfying assignment for all instances of such problems. The complexity arises from the fact that there are infinitely many potential solutions, making it challenging to determine whether a feasible assignment exists or not. To find a satisfying assignment for linear inequalities, algorithms typically use heuristics or approximation techniques that do not guarantee optimality or completeness. Various methods, such as linear programming or constraint satisfaction algorithms, can be employed, but they may have exponential time complexity in the worst case. Therefore, solving a set of linear inequalities generally requires more computational resources and time compared to solving linear equalities.

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Answer:

51 degrees

Step-by-step explanation:

As we already know that this triangle is a right triangle.

To find x, you need to subtract both angles.

90 - 39

= 51

Answer:n=−2

Step-by-step explanation:

The measure of the third angle, C, is 30 degrees. So, the correct answer is (c) 30.

Let's assume the three angles of the triangle are A, B, and C, where A, B, and C are measured in degrees.

We know that the sum of the angles in a triangle is 180 degrees. Therefore, we can write the equation:

A + B + C = 180

The obtain of two angles is 150 degrees, we can set up another equation:

A + B = 150

To obtain the measure of the third angle, which we'll call C, we can subtract the sum of the other two angles from 180:

C = 180 - (A + B)

Substituting the value of the sum of two angles (150 degrees), we have:

C = 180 - 150

C = 30

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Answer:

Where is ur question??

plss put ur question I will give correct answer

The  steps to draw a pipeline diagram for a given program are:

Understand the CPU architecture: This involves knowing pipeline stages, their durations, and relevant instructions/hazards. Step 2: Identify program instructions. Each instruction goes through pipeline stages.

Assign cycle numbers sequentially to each instruction. Visualize pipeline progress over time. Draw pipeline stages. Draw a horizontal line divided into cycles to represent time. Each cycle = 1 clock cycle duration. Place cycle numbers below the line.

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Answer:

3. Likely

Step-by-step explanation: