If the first term of a G.P. is 8 and its common ratio is -2. The 3^rd term of this G.P. is :

1. -32

2. 2

3. 32

4. -2

The 4^th term of a G.P. is 16 and the 7^th term is 128, then its common ratio is equal to :

1. 2

2. -2

3. 1

4. -1