To find the change in temperature from 9 a.m. to noon, we can set up an equation. Let's denote the temperature at 9 a.m. as \( T_1 \) and the temperature at noon as \( T_2 \).
Given:
- \( T_1 = -5.8 \) degrees Celsius
- \( T_2 = -1.6 \) degrees Celsius
The change in temperature \( \Delta T \) can be calculated using the formula:
\[ \Delta T = T_2 - T_1 \]
Substituting the values:
\[ \Delta T = (-1.6) - (-5.8) \]
This simplifies to:
\[ \Delta T = -1.6 + 5.8 \]
Calculating the numeric value:
\[ \Delta T = 4.2 \]
So, the change in temperature during these three hours is \( 4.2 \) degrees Celsius.
Explanation of the Answer:
The positive value of \( 4.2 \) degrees Celsius indicates that the temperature has increased by \( 4.2 \) degrees from 9 a.m. to noon. This means that despite starting off at a cold \( -5.8 \) degrees Celsius in the morning, the temperature has warmed up to \( -1.6 \) degrees Celsius by noon, showing a significant rise in the air temperature during this three-hour period.