An investigator modeled the physiological cooling effect of vasodilation and sweating using two brass cylinders filled with hot water. Cylinder P was wrapped in a water-saturated porous membrane to simulate sweating skin, while Cylinder Q was wrapped in a completely dry porous membrane. Both cylinders were placed in a draught-free room at 18 ∘C18\text{ }^{\circ}\text{C}18 ∘C, and their core temperatures were recorded over 14 minutes as shown in the table below.
| Time (minutes) | Cylinder P (saturated membrane) temperature (°C) | Cylinder Q (dry membrane) temperature (°C) |
|---|---|---|
| 2 | 88 | 86 |
| 4 | 74 | 81 |
| 6 | 62 | 76 |
| 8 | 51 | 71 |
| 10 | 41 | 66 |
| 12 | 33 | 61 |
| 14 | 28 | 56 |
Calculate the rate of temperature change in Cylinder P from 2 to 14 minutes.
