1. Determine the nth term of the geometric sequence 1,2,4,8,...

The nth term is___________

2. find the common ratio 2/3, -8/3, 32/3, -128/3,...

The common ration is_______________

3. A theater has 24 rows of seats. The first row has 15 seats, the second row has 17 seats, the third row has 19 seats, and so on. How many seats in the theater? ____________________

4. If an arithmetic series has a1=2, d=-5 and n=31 What is sn? S31=________________________

5. Find a1 when d=2 and a6=1

a1=__________________