hey guys can anyone help me with question b) c) and d) i am really confused for some reason i am not getting the correct answer.

18) Twenty-Four girls try out for the senior softball team at St. Marcellinus. In how many ways can a team of 9 fielders (1 pitcher, 1 Catcher, 4 Infielders, 3 Outfieders) be selected given each of the following conditions?

a) any girl can play any position.

so for a) it is 24C9 = 1 307 504

b) Of the girls trying out are Pitchers, 5 are Catchers and the other trying out play any of the other 7 field positions.

c) Emily must be pitcher and Jeannie must be the catcher, but the other girls can play any other position.

d) Louise cannot be on the team

the answers to :

b) 194 480

c) 170 544

d) 817 190

Thanks in advance