Question 657938
From 26 Student 4 student can be selected which can be seen as making combination of 4 out of 26 things, so will be result as 26C4 which will give us (26!/(4!22!), Calculating this will give us 14950.

 (a) All 4 work are differenct from each other (Produce, script writing,acting and running camera ) so after seleting 4 ,these 4 work can be done in total 4*3*2*1 , as after selecting one for one specific task he will be no more available for another task. 

( Explanation : - Let say first we are selecting for script writing so now the person can no more participate in acting, production or running camera )

so after selection 4 places can be filled in 12 ways.  

(b) Since Selecting 4 out of 26 and than selecting role for each one are independent of each other. so total possible ways to represent in act are 12*14950 = 179400 ( Wooo.. too big number.. But this is what you expect when you have too many option to fill 4 things ) 

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