7 a cold front comes in and the temperature d...
7 a cold front comes in and the temperature decreases 4°f every hour. what is the change in temperature after 7 hours? a. 28°f b. 3°f c. -3°f d. -28°f
Answer
# Explanation:
## Step1: Identify the rate and time
The rate of temperature - decrease is 4°F per hour, and the time is 7 hours.
The rate is negative since the temperature is decreasing, so the rate $r=- 4^{\circ}F$ per hour and time $t = 7$ hours.
## Step2: Calculate the change in temperature
The change in temperature $\Delta T$ is given by the product of the rate and the time, i.e., $\Delta T=r\times t$.
Substitute $r=-4$ and $t = 7$ into the formula: $\Delta T=-4\times7=-28^{\circ}F$.
# Answer:
D. $-28^{\circ}F$