Which circumstances could be sources of error within the experiment? check all that apply

What does si stand for,when referring to a system of measurement

The radius of a sphere is increasing at a rate of 9 cm/ sec. find the radius of the sphere when the volume and the radius of the sphere are increasing at the same numerical rate.

Apotter's wheel moves uniformly from rest to an angular speed of 0.20 rev/s in 32.0 s. (a) find its angular acceleration in radians per second per second. rad/s2 (b) would doubling the angular acceleration during the given period have doubled final angular speed?