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3 years ago

5

____________ occurs when an energy source transfers heat directly to another object through space; an example would be an object

becoming warm by sitting in the sunshine.

2 answers:

wel3 years ago

7 0

I believe it is radiation

Ludmilka [50]3 years ago

7 0

Answer:

B.

Step-by-step explanation:

You might be interested in

A lumber company is making boards that are 2920.0 millimeters tall. If the boards are too long they must be trimmed, and if the

Effectus [21]

Answer:

The value of the test statistic is of 0.22.

Step-by-step explanation:

Our test statistic is:

$t = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the expected mean, $\sigma$ is the standard deviation(square root of the variance) and n is the size of the sample.

A lumber company is making boards that are 2920.0 millimeters tall.

This means that $\mu = 2920$ .

A sample of 12 is made, and it is found that they have a mean of 2922.7 millimeters with a variance of 121.00.

This means that $X = 2922.7, n = 12, \sigma = \sqrt{121} = 11$ . So

$t = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$t = \frac{2922.7 - 2922}{\frac{11}{\sqrt{12}}}$

$t = 0.22$

The value of the test statistic is of 0.22.

4 0

2 years ago

4. A book club earns $230 for its meetings. They want to divide the money to pay for 7 meetings. When the treasurer types 230 ÷

DIA [1.3K]

Answer:

to the tenths place, 32.86

Step-by-step explanation: It is because money is always rounded to the tenths place

4 0

3 years ago

Two brothers have a total age of 28 if one brother is older by 20 years how old is the second brother

svlad2 [7]

Answer:

8

Step-by-step explanation:

Total meaning addition, you would use the opposite operation to find the answer.

28 - 20 = 8

And to check your work you would add;

20 + 8 = 28

which is the brothers total combined age.

6 0

3 years ago

Read 2 more answers

Find the equation of a line that passes through the point (-2,1) and has a gradient of -3.

zavuch27 [327]

A straight line passing through the point (-2,1) and having a gradient of -3 yields the equation y = -3x - 5.

We know that a straight line is an infinitely long line with no curves on it. A straight line's equation is

y = mx + c...(1), where m is the gradient of the straight line and c is a constant.

Given that the gradient of the given straight line = m = -3.

Putting this value in (1), we get

y = -3x + c ...(2)

Again, the given straight line passes through the point (-2,1). So, we can put x = -2 and y = 1 to get the value of the constant c.

So, 1 = (-3)(-2) + c

i.e. 6 + c = 1

i.e. c = 1 - 6 = -5

(2) can be written as

y = -3x - 5

Therefore the equation of the given straight line is

y = -3x - 5

Know more about straight lines here -

brainly.com/question/8085796

#SPJ10

6 0

2 years ago

A quality control expert at LIFE batteries wants to test their new batteries. The design engineer claims they have a variance of

iris [78.8K]

Answer:

The probability that the mean battery life would be greater than 533.2 minutes (in a sample of 75 batteries) is $\\ P(z>0.48) = P(x>533.2) = 0.3156$

Step-by-step explanation:

The main thing we have to take into account in this question is that we are about to find the probability of a <em>sample mean</em>. The distribution for <em>sample means</em> follows a <em>normal distribution</em> with mean $\\ \mu$ and standard deviation $\\ \frac{\sigma}{\sqrt{n}}$ . Mathematically

$\\ \overline{x} \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

For values of the sample $\\ n \ge 30$ , no matter the distribution the data come from.

And the variable <em>z</em> follows a <em>standard normal distribution</em>, and, as we can remember, this distribution has a mean = 0 and a standard deviation = 1. Mathematically

$\\ z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$ [1]

That is

$\\ z \sim N(0, 1)$

We have a variance of 3364. That is, a <em>standard deviation</em> of

$\\ \sigma^2 = 3364; \sigma = \sqrt{3364} = 58$

The population mean is

$\\ \mu = 530$

The sample size is $\\ n = 75$

The sample mean is $\\ \overline{x} = 533.2$

With all this information, we can solve the question

The probability that the mean battery life would be greater than 533.2 minutes

Using equation [1]

$\\ z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

$\\ z = \frac{533.2 - 530}{\frac{58}{\sqrt{75}}}$

$\\ z = \frac{3.2}{\frac{58}{8.66025}}$

$\\ z = \frac{3.2}{6.69726}$

$\\ z = 0.47780$

With this value of z we can consult a <em>cumulative standard normal table</em> (or use some statistic program) to find the cumulative probability for <em>z</em> (and remember that this variable follows a standard normal distribution).

Most standard normal tables have values for z for only two decimals, so we can round the previous value for z as z = 0.48.

Then

$\\ P(z$

However, in the question we are asked for $\\ P(z>0.48) = P(x>533.2)$ . As well as all normal distributions, the standard normal distribution is symmetrical around the mean, and we have

$\\ P(z>0.48) = 1 - P(z$

Thus

$\\ P(z>0.48) = 1 - 0.68439$

$\\ P(z>0.48) = 0.31561$

Rounding to four decimal places, we have

$\\ P(z>0.48) = 0.3156$

So, the probability that the mean battery life would be greater than 533.2 minutes is (in a sample of 75 batteries) $\\ P(z>0.48) = P(x>533.2) = 0.3156$ .

5 0

3 years ago