Answer:
m = 57t, where the units of measurement of 57 are mph and that of t is hr.
Explanation:
Use the given info to find the speed of the train, which is a unit rate:
95 miles 95 mi
------------------ = ------------- = 0.95 mile/min
1 hr 40 min 100 min
Better yet, use hours, not minutes.
95 miles 95 mi
------------------ = ------------- = 57 mph
1 hr 40 min 1 2/3 hr
Then m(t) = (rate)(time) = (57 mph)t This corresponds to Answer D.