1. Describe that the subset H={1, -1} of Z is a group under multiplication
2. Compute the order of the following groups a) Z27 b) D6
3.In Z15 under addition modulo 15 find, <3> and <4>
4. Let x belong to a group and lxl = 6 Find lx^2l, lx^3l, lx^4l, and lx^5l