There are 10 chips in a bag: 4 have the number 1 written on them, 2 the number 2, and 4 the number 3. Suppose each chip is drawn with the same probability. Let X be the number on the chip that is selected.

1. Find the sample space of X

2. Find the p.m.f. (probability mass function) of X

3. Compute E [X] (expected value)

4. Compute Var [X] (Variance)

Please help? I will forever thank you. this is all so confusing to me.