What is the approximate percent change in temperature that went down from 120 degrees to 100 degrees?

Greg is designing a clock face. using the center of the clock as the origin, he keeps its diameters at 10 units. match the positions for the hours on the clock face to their corresponding coordinates. 3 o'clock (0,-5) 6 o'clock (5,0) 9 o'clock (0,5) 12 o'clock (-5,0)