Chapter 13 - Partial Derivatives - 13.1 Functions Of Two Or More Variables - Exercises Set 13.1 - Page 914: 16

relative humidity $\approx 77+(1 / 5)(79-77)=77.6 \%$

Plugging in the given values into the equation: \begin{array}{l} \text { (a) } \\ \qquad 4^{\circ} \mathrm{C} \\ \text { (b) } \\ \text { relative humidity } \approx 62-(1 / 4) 9=59.75 \% \\ \text { (c) } \end{array} relative humidity $\approx 77+(1 / 5)(79-77)=77.6 \%$