++++++++|||||||||Can you please check whether or not my answers are correct and if not, can you fix them for me?

Question

Find the sum and state whether it converges or diverges?

1) 0.1 + 0.05 + 0.025 + 0.0125 + ...

My answer: converges, | r | < 1

2)6 + 2.4 + 0.96 + ...

My answer: diverges, r = 0.4

c) 1 - 2 + 4 - 8 + ...

r = -2

My answer: diverges, r < -1

Thanks

Answer 1

2) converges, the other answers are correct