4. The height h in centimeters of Shuntaro's pogo stick from the ground as he jumps on it since s seconds have passed is roughly modelled by the equation h(s) = sin 4x + 2sin4x + 1. a. How many times does Shuntaro hit the ground in the first 5 seconds? [A2] b. How many centimeters is Shuntaro off the ground after 2 seconds? [A2] c. During the first second, when is Shuntaro 2.5cm to two decimal places? [A3]