4 A camera shop stocks eight different types of batteries on

4. A camera shop stocks eight different types of batteries, one

of which is type A7b. Assume there are at least 30 batteries

of each type.

a. How many ways can a total inventory of 30 batteries be

distributed among the eight different types?

b. How many ways can a total inventory of 30 batteries be

distributed among the eight different types if the inventory

must include at least four A76 batteries?

c. How many ways can a total inventory of 30 batteries be

distributed among the eight different types if the inventory

includes at most three A7b batteries?