A three$-$step process is used to make a product. The yield of step $1$ is $90\%$; of step $2,70\%$; and of step $3$ is $50\%.$ What is the yield of the overall process?

Question $3$Answer

a$.$

$70\%$

b$.$

Cannot be determined

c$.$

$40\%$

d$.$

$31\mathrm{.}5\%$