Answer:
it is decreasing in the time interval 0<x<2 hours.
Explanation:
Graph of first line going through ordered pairs A(0, 40) and B(2, 10).
Graph of second line going through ordered pairs B(2, 10) and C(4, 10). Graph of third line going through ordered pairs C(4, 10) and D(7, 50).
When movement is from point A to B, change in x = 2 and change in y = -30
Hence change for unit x = -30/2 = -15 ... i
When movement is from point B to C, change in x = 2 and change in y = 0
Hence change for unit x = 0/2 = 0 ... ii
When movement is from point C to D, change in x = 3 and change in y = +40
Hence change for unit x = 40/7 = 5.71 .. iii
Hence from A to B it is decreasing, B to C it remains constant and C to D it is increasing.
x coordinate represents hours and y coordinate degrees.
Hence answer is it is decreasing in the time interval 0<x<2 hours.