Two cases of soft drinks, 24 bottles of one type and 24 of another, are distributed among

Question:

Two cases of soft drinks, 24 bottles of one type and 24 of another, are distributed among five surveyors who are conducting taste tests. In how many ways can the 48 bottles be distributed so that each surveyor gets
(a) at least two bottles of each type?
(b) at least two bottles of one particular type and at least three of the other?