[Bassel]

since it is an SN1 I first thought to look at the stabilities of the carbocat ions. since the are the same and there is no shifting I looked at the steric effect so i think that cpd A is the one reacting faster because it has less steric effect. is that true ? is it the right way of thinking in like these questions?

[orgopete]

I think the compound with higher energy, higher strain, will react faster.

[Kate]

Yep, I think so too.

The best way to figure it out is to construct the chair conformation of A and B and see which one is less stable by looking at the axial position of Br. 

[rasoooool]

Yep, I think so too.

The best way to figure it out is to construct the chair conformation of A and B and see which one is less stable by looking at the axial position of Br.

correction answer.