The table below gives the average temperature, T, at a depth d, in a borehole in Belleterre, Quebec.
d, depth (m) T, temp (C∘)
25 5.50
50 5.20
75 5.10
100 5.10
125 5.30
150 5.50
175 5.75
200 6.00
225 6.25
250 6.50
275 6.75
300 7.00
Evaluate ΔT/Δd on the following intervals

a) 50≤d≤175 ΔT/Δd =


b) 100≤d≤250 ΔT/Δd =


c) 75≤d≤125 ΔT/Δd =