Chapter 1 - Introduction, Measurement, Estimating - Problems - Page 19: 37

a) $\frac{[L]}{{[t]^4}}$ , $\frac{[L]}{[t]^2}$ b) $\frac{m}{s^4}$ , $\frac{m}{s^2}$

a) Values can only be subtracted/added if the units are consistent. Thus A and B must have dimensions which will eventually result in the dimensions of velocity $\frac{[L]}{[t]}$ b) Replace each dimension obtained in part a) with its corresponding SI units.