The rate of heat loss, Qloss through a window is a function of the temperature difference T,

Question:

The rate of heat loss, Qloss through a window is a function of the temperature difference ΔT, the surface area A, and the R resistance value of the window (in units of ft2⋅hr⋅°F/Btu): Qloss = fcn (ΔT, A, R). (a) Rewrite in dimensionless form. (b) If the temperature difference doubles, how does the heat loss change?