Suppose there is only 1 pizzeria in Smalltownsville and it is therefore a monopolist. The pizzeria has no fixed costs and a constant marginal cost equal to $3 per pepperoni pizza. It faces the following demand schedule:

Price per unit $42 $38 $32 $30 $26 $20 $16 $12

Quantity demanded 1 2 3 4 5 6 7 8

a) The pizzeria's marginal revenue (in $) for the third pizza is ______ (please input only a number, no dollar signs or other symbols)

b) The profit-maximising price for this pizzeria is $_______(please input only a number, no dollar signs or other symbols)