Explain a cyclothem and how they relate to coal formation and ice ages in the past.

Witch one is it soo it the the question b.a,b,c,d

If the basis of an isosceles trapezoid have lengths of 11 and 26, what is the length of the median?

This is a 2017 topographic map of puerto rico in the united states, and i'm sorry that people there have suffered such a disaster. i want to ask, what do the yellow dots and areas represent on this graph? and the blue area and the little blue circle, and the little blue sign that looks like a signal tower, what do they stand for?