Joey rode his bike over a piece of gum. Joey continued riding at a constant rate. At time t = 1.25 seconds, the gum was at a maximum height above the ground and 1 second later the gum was at a minimum. If the diameter of the wheel ( all the way out to the edge of the tire) is 68 cm, create an equation that will allow for the prediction of the height of the gum in centimeters at any time t.

a) Find the height of the gum when Joey gets to the corner at t = 15.6 seconds, assuming he maintains a constant speed.

b) Find the first and second time the gum reaches a height of 12 cm while Joey is riding at a constant rate

Known: t = 2.25 seconds, Joey is at a minimum
Since d = 68 cm, r = 34 cm, circumference = 68pi cm
So he moves 68 pi cm every second?

I need help on creating a equation though, and I think part b requires drawing a triangle or 2 if I'm correct? Any help is appreciated as always