(a(i))[1]
Define what pressure is.
(a(ii))[1]
Show that the SI base units for pressure are $\text{kg m}^{-1}\text{s}^{-2}$.
(b)[3]
A gas moves through the narrow end (nozzle) of a pipe. For certain conditions, the mass $m$ of gas passing through the nozzle in a short time $t$ is given by $\frac{m}{t} = kC\sqrt{\rho P}$, where $k$ is a constant with no units, $C$ is a quantity that depends on the nozzle size, $\rho$ is the density of the gas reaching the nozzle, and $P$ is the pressure of the gas reaching the nozzle. Determine the base units of $C$.