Exercise 1:
The easiest way to compute powers of complex numbers is to write them in the form

In this form, you have

The magnitude of the number is given by

So, we have

As for the angle, we have

So, we have

Finally,

Exercise 2:
You simply have to compute the trigonometric function:

So, we have

Answer: 119.57 cu. ft.
Step-by-step explanation:
Volume of a hemisphere = (2/3)πr^3
= (2/3) * 22/7 * 3.85^3
If the triangles are similar, the base should be 24 inches. The legs on the first triangle are 12 inches. To get 36 inches (the other triangle), we multiply 12 by 3. 12 x 3 = 36. Because you did that to the legs, you must also do it to the base. 8 x 3 = 24. Therefore, the base of the second triangle is 24 inches.
Answer:
D.
Step-by-step explanation: