How to find rate of speed on graph

Speed is equal to distance divided by time, therefore on a distance time graph, the speed is the gradient of a line. To find the gradient, find two points on the graph, (x1, y1) and (x2, y2).

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation:

thats a little if u want the answer just look it up on google thats what i do haha : )