The Speed of a Vehicle Varies Inversely as the Time $\frac{45}{2} \mathrm{mph}$

Multiple Choice

The speed of a vehicle varies inversely as the time it takes to travel a fixed distance. If a vehicle travels a fixed distance at 40 miles per hour in 45 minutes, how fast must it travel to cover the same distance in 20 minutes?

A) $\frac{45}{2} \mathrm{mph}$
B) $90 \mathrm{mph}$
C) $\frac{160}{9} \mathrm{mph}$
D) $\frac{9}{160} \mathrm{mph}$