Question

at what time was the incline at 1.71m, if it is at 1.9m now and at 1.4m one hour ago? (assuming that it declining evenly at the same rate)

Answer 1

Assuming even change in height, the rate is

0.5 m/hr

So, at what time t do you have

1.4 + 0.5t = 1.71
??