A statistics teacher started class one day by drawing the names of 10 students out of a hat and asked them to do as many pushups as they could. The 10 randomly selected students averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the distribution of the population of number of pushups that can be done is approximately normal. The 95% confidence interval for the true mean number of pushups that can be done is

a. 13.02 to 16.98.
b. 8.56 to 21.40.
c. 11.31 to 18.55.
d. 5.75 to 24.25.

 b. 8.56 to 21.44

Step-by-step explanation:

Let   be the  mean number of pushups that can be done.

As per given , we have

Sample size : n= 10

Degree of freedom = n-1=9

Sample mean :

Sample standard deviation :

Significance level : α=1-0.95=0.05

From t- distribution table ,

Critical two -tailed t-value for α=0.05 and df = 9 is

Confidence interval for is given by :-

Hence, the  95% confidence interval for the true mean number of pushups that can be done is 8.56 to 21.44.

the workers who do no drive has no reasonable reason to buy gasoline due to they don't have anything to use it for

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: