In Exercise, solve the given problems. All data are accurate to two significant digits unl...

In Exercise, solve the given problems. All data are accurate to two significant digits unless greater accuracy is given.

A helicopter used in fighting a forest fire travels at 105 mi/h from the fire to a pond and 70 mi/h with water from the pond to the fire. If a round-trip takes 30 min, how long does it take from the pond to the fire? See Fig. 1.22.

Fig. 1.22