Answer:
A) 1525
B) 4636
C) 8479
Step-by-step explanation:
Lest say that The book had been sold x copies in the period of June 1990-June 1995. And we know that the book had been sold 152*x/100 copies in the period of June 1995–June 2000. By June 2000 in total 3843 book had been sold. Therefore number of the copies that sold in the period of June 1990-June 1995 is:

number of the copies that sold in the period of June 1995-June 2000 is:

For the period June 2000–June 2005 2318*2=4636 book had been sold.
For this case what you must do is to determine the value of r of the given equation:
A = pi * r ^ 2.
Clearing the value of r we have:
r = root (A / pi)
Note that r has two roots:
r1: = + root (A / pi)
r2: = - root (A / pi)
In this case we must ignore the negative root.
Answer:
The formula to find r is
r = root (A / pi)
B) thats the only one i could think of that would even sound right
Volume of a cylinder = πr^2 h = π x (2)^2 x 3 = π x 4 x 3 = 12π = 37.7 cm^3