## Elementary Technical Mathematics

The temperature at $10:00\text{ AM}$ from the hygrothermograph is ${{80}^{\circ }}\text{F}$.
The upper part records temperature, which ranges from ${{10}^{\circ }}\text{F}$ to ${{110}^{\circ }}\text{F}$ in the hygrothermograph. By looking at the given graph, it can be seen that at $10:00\text{ AM}$, the upper horizontal line cuts the $10:00\text{ AM}$ vertical line at ${{80}^{\circ }}\text{F}$.