In the game Text Twist, 6 letters are given and the player must form words of varying

Question:

In the game Text Twist, 6 letters are given and the player must form words of varying lengths using the letters provided. Suppose that the letters in a particular game are ENHSIC.
(a) How many different arrangements are possible using all 6 letters?
(b) How many different arrangements are possible using only 4 letters?