Answer:
a

b
Step-by-step explanation:
From the question we are told that
The daily demand is 
The standard deviation is 
The service probability is 
The number of chips in the inventory is 
The number of days in his monthly is 
The lead time is 
Generally the number he should order (optimal order ) is mathematically represented as

Here
is the monthly standard deviation which is mathematically evaluated as

=> 
=> 
Also z-value for the 95% service probability from the z-table is 1.96
So

=> 
For the maximum order quantity k = 0
So

=>
=>