The problem that follow involve straight-line motion. The time t is in seconds unless othe...

The problem that follow involve straight-line motion. The time t is in seconds unless otherwise stated.

Problem

A zoology graduate student is provided with a bow and an arrow tipped with a syringe of sedative and is assigned to measure the temperature of a black rhinoceros (Diceros bicomis). The range of his bow when it is fully drawn and aimed 45° above the horizontal is 100 m. A truculent rhino suddenly charges straight toward him at 30 km/h. If he fully draws his bow and aims 20° above the horizontal, how far away should the rhino he when the student releases the arrow?