Help plz :)

Determine the measure of each unknown angle using the diagram.

Find the solution set of this inequality. enter your answer in interval notation using grouping symbols. |8x-4| ≤ 12

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

This is a map of the mars exploration rover opportunity predicted landing site on mars. the scale is 1cm : 9.4km. what are the approximate measures of the actual length and width of the ellipse? i mostly need to know how to set it up : )