Help me with my physics wrok please

Find the volume of the ellipsoid x^2+y^2+5z^2=36.

Which changes of state do the labels represent? a: b: c:

Suppose a wheel with a tire mounted on it is rotating at the constant rate of 2.15 times a second. a tack is stuck in the tire at a distance of 0.373 m from the rotation axis. noting that for every rotation the tack travels one circumference (a) find the tack's tangential speed. (b) what is the tacks radial acceleration?