Galileo discovered that the period of a pendulum depends only on the length of the pendulu...

Galileo discovered that the period of a pendulum depends only on the length of the pendulum and the acceleration of gravity. The period T of a pendulum (in seconds) is

where l is the length of the pendulum in feet and g ≈ 32.2 ft/sec2 is the acceleration due to gravity. Find the period of a pendulum whose length is 4 feet.