Question

15 Points!

Answer 1

$S(p)=D(p)\to10+0.002p^3=50-0.04p^2\\\\0.002p^3+0.04p^2-40=0\ \ \ |\cdot1000\\\\2p^3+40p^2-40000=0\ \ \ \ |:2\\\\p^3+20p^2-20000=0\to p\approx21.86$

Answer: A) $21.86