318.5
13 x 7 x 7/2 = 318.5 inches
Follow the formula
We can find the height of the altitude by the ratio of sin. See my attachment.
sin of angle = side in front of the angle / hypotenuse
sin x = height/distance
If the two pilot is rising in an hour, then the first distance is 400 miles, the second distance is 300 miles.
Find the height of first pilotheight/distance = sin x
height/400 = sin 30°
height = sin 30° × 400
height = 1/2 × 400
height = 200
Find the height of second pilotheight/distance = sin x
height/300 = sin 40°
height = sin 40° × 300
height = 0.642 × 300
height = 192
So the first pilot traveling 400 mph with 30° is more quickly to reach high altitude than the second pilot traveling 300 mph with 40°
B. (n + 15) x 3--- That seems to be the correct answer. I hope I helped!
To obtain an estimate of a parameter of a population, we use confidence intervals.
Confidence intervals:
The larger the sample size, the closest the parameter estimate is to the value of the population, as the margin of error of confidence intervals is inversely proportional to the sample size, that is, a greater sample leads to a smaller margin of error.
Thus, you should select the highest sample size in the options.
For more on confidence interval/margin of error, you can check brainly.com/question/22718960