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SOLVE THE FOLLOWING PROBLEMS.
A) IN HOW MANY WAYS CAN THE LETTERS OF THE WORD “TRACK” BE ARRANGED?
B) A STUDENT MUST SELECT AND ANSWER SIX OUT OF TEN QUESTIONS ON AN EXAM. IN HOW MANY WAYS CAN THIS BE DONE?
C) A TEACHER DECIDES TO GIVE SIX IDENTICAL PRIZES TO 6 OF THE 20 STUDENTS IN HIS CLASS. IN HOW MANY WAYS CAN THIS BE DONE