Complete Question
The complete question is shown on the first uploaded image
Answer:
a
The effect of a change in the price of a new pair of headphones on the equilibrium price of replacement tips ( dp/dpN) is

b
The value of Q and p at equilibruim is
and
5
The consumer surplus is 
The producer surplus is 
Explanation:
From the question we are told that
The inverse market demand is 
The inverse supply function is 
a
The effect of change in the price is mathematically given as

Now differntiating the inverse market demand function with respect to 
We get that

b
We are told that
$30
Therefore the inverse market demand becomes

At equilibrium

So we have

Where
is the quantity at equilibrium



Substituting the value of Q into the equation for the inverse market demand function

5
Looking at the equation for
we see that
For Q = 0


And for Q = 250


Hence the consumer surplus is mathematically evaluated as

Substituting value


And
The producer surplus is mathematically evaluated as

