Answer:
do the reverse of pie r squared
Step-by-step explanation:
Answer:
A. T > 2.539
Step-by-step explanation:
We have a hypothesis test of the mean, with unknown population standard deviation.
The hypothesis are:

From the hypothesis we can see that the test is right-tailed, so the critical value of t should be a positive value.
The degrees of freedom can be calculated as:

The significance level is 0.01, so the critical value tc should be the one that satisfies:

Looking up in a t-table, for 19 degrees of freedom, this critical value is tc=2.539.
Answer:
- 6.04 km (per angle marks)
- 5.36 km (per side hash marks)
Step-by-step explanation:
Going by the angle indicators, the ratios of corresponding sides of the similar triangles are ...
x/2000 = 4200/3500
x = 2000·6/5 = 2400 . . . . yards
Then the distance of interest is ...
(2400 yd + 4200 yd)×(0.0009144 km/yd) = 6.6×.9144 km
= 6.03504 km ≈ 6.04 km
_____
Going by the red hash marks, the ratios of corresponding sides of the similar triangles are ...
x/2000 = 3500/4200
x = 2000·(5/6) = 5000/3 . . . . yards
Then the distance of interest is ...
(5000/3 + 4200) yd × 0.0009144 km/yd ≈ 5.36 km
_____
<em>Comment on the figure</em>
The usual geometry here is that the outside legs (opposite the vertical angles) are parallel, meaning that the angle indicators are the correct marks. It is possible, but unusual, for the red hash marks to be correct and the angle indicators to be mismarked. The red hash marks seem tentatively drawn, so seem like they're more likely to be the incorrect marks.