Indica or Sativa?

This is my first time growing and I am unsure if I have indica or sativa plants. I used seeds that were in some weed I got a while back and I am unsure of the strain I have. Can anyone answer the following questions?

1.) How can you tell what kind of plant you are growing (indica or sativa)?
2.) How soon can you tell (shape of leaf etc)?

Here are a few pics of my babies. Any advice would be much appreciated.

Too hard to say right now, thinner leaf blades are usually sativa, thicker are usually indica, but there are always exceptions to the rule. They do kinda look like one ive got goin right now.

I would say you have a bit of a hybrid, but to me it looks mainly indica, I would imagine your flowering time will be between 8 & 10 weeks