Answer:
4/5
Step-by-step explanation:
F(C) = 9/5C + 32
I'll just change F(C) to y and 9/5C to 9/5x.
y = 9/5x + 32
inverse...
x = 9/5y + 32
9/5y = x - 32
y = 5/9x - 160/9
Sooooo
F(C) = 5/9C - 160/9
Recall that distance = speed times time. Thus, time = distance / speed.
Here:
time = distance / speed = 0.8 km / 12 km/hr = 1/15 hr.
Note that 1/15 hr = 1/15 (60 min) = 4 minutes
Negative numbers aren't considered in any of those categories.