Question $2(2+2+2+2+2=10$ points$)-$ Normal demand for newsvendor model

Consider a clothing item satisfying assumptions of the newsvendor model:

Demand $$ Normal $=100,=20.$

The wholesale cost is $$20/$unit$.$ For every unit sold, there is a profit of $$10$ per unit $($Revenue $=$

cost $+$ profit $=20+10=$$$30).$ Unsold units are disposed. For every leftover unit, there is a loss

of $$\frac{5}{?}$ unit. $($Loss $=$ cost $-$ salvage value$)$

a$.)$ What is the mean demand?

b$.)$ What is the newsvendor critical ratio?

c$.)$ What is the optimal order quantity $Q^{**}?($Round up to the nearest integer if you get a non$-$

integer.$)$

d$.)$ If we order $Q^{**}$ as obtained in $($c$),$ what is the expected lost sales?

e$.)$ If we order $Q^{**}$ as obtained in $($c$),$ what is the expected profit?