Really depends on what you combine it with. I do it alongside maths, fm and physics and this is quite a popular option. Can lead to a really broad range of degree choices.
1. Not much maths involved. The most you're going to have to do is calculate percentage changes and then apply to a formula.
2. Not hard if you know basic GCSE maths.
3. Definitely more essay based. There are some maths questions but they are usually quite a small proportion of the total marks in the paper.