Anyone able to help me with this question please?

The power required by a helicopter when hovering depends only upon the vertical thrust (a force) F provided by the blades, their length l, and the mass density of air, ρ.

a) Establish an equation that relates the helicopters power requirement to these three quantities.

b) By what factor is the power requirement increased such that the helicopter can maintain a constant altitude when it takes on a load that doubles its weight?

We have been doing questions to show the SI units on the left hand side of an equation match the right hand side. These are more advanced questions we are given to manipulate the variables of an equation to match the SI units of the subject of the equation. Part a talks about power depending on F, l and p. The SI units for power are kgm^2s^-3 whereas F, l and p on their own are kg^2m^-1s^-2.

It seems like a complete mess trying to get F,l and p to the right powers to match SI units on the left for power. Any advice on how to do it? Or an easier way to do it? I just keep adding powers and it never seems to balance

Thanks!

Sorry if this is the wrong place to put this type of question I have only just joined.