Help guys this ALEKS 6th grade math

The surface area (sa) of a cube with a as the length of each of its sides is given by the formula . if the surface area is known, how can you rewrite the formula to find its side?

Julia is going for a walk through the neighborhood. what unit of measure is most appropriate to describe the distance she walks?

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny