Which equation could be used to solve the problem?

joan picked 4 bushels of apples in one hour.

at that rate, how many bushels would she pick in 8 hours (b)?

a.
b = 8 ÷ 4

b.
b = 4 ÷ 8

c.
b = 8 + 4

d.
b = 8 • 4