1. A multiple-choice exam has 20 questions, each with four possible answers and 10 questions with five possible answers. How many different answer are possible (if you include not answering any or some of the questions)?

2.If the first 20 questions are 4 points each and the next 10 questions are 2 points each, how many ways can someone get exactly 90% in this exam?

3. How many ways can we select a congressional committee of 4 members from 5 Democrats, 5 Republicans, and 5 Independents such that:

a.There is at least one independent in the committee.

b.There is exactly one Democrat in the committee.

c.It cannot include both Democrats and Republicans.

d.It must have at least one Democrat and at least one Republican.