Suppose we have a pendulum that is "y" feet long. Our pendulum makes one complete swing in "t" seconds. Assume "y" and "t" are related by the formula...

Suppose we have a pendulum that is "y" feet long. Our pendulum makes one complete swing in "t" seconds. Assume "y" and "t" are related by the formula y = .9 t^2. If the pendulum is less than 4 feet long, what is the range of values for "t"?