Approximately how many atoms are there along a 9.5 cm line

An object is moving east, and it’s velocity changes from 65m/s to 25m/s in 10 seconds. which describes the acceleration?

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?

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c