$4\mathrm{.}1$ Simulating the News Dealer$$s Problem

Consider the following demand distribution instead of the one provided in the book:

Demand $($D$)$ Probability $($P$\_$D$)$

$550\mathrm{.}2$

$650\mathrm{.}3$

$750\mathrm{.}3$

$850\mathrm{.}2$

What is the best order quantity among values of $50$ and $70?$