Hey guys i am currently in Uni studying civil engineering and i'm having trouble with one of the question and would really appreciate some help.

This is the question;

If the net radiation in a day is 20 MJ/m^2 and the latent heat lost with evaporation is 15MJ/m^2, a well mixed 2m deep lake will heat up in one day by (choose the closest value):

a) 0.6 degrees Celsius

b) 2.39 degrees Celsius

c) 1.20 degrees Celsius

d) 0.006 degrees Celsius

e) 0.0005 degrees Celsius

(assume conductive heat fulx (Q)=0; Cp = 4.18 KJ/kg/degrees Celsius and pw=1000kg/m^3)

These are the formula i know;

A.Rn =dmv/dt*(hlg) +dT/dt*Cp m ± Q

and

dmv/dt = B ρw (Pvap,sat − Pvap )A

I can't seem to figure it out since they haven't given you the Temperature.

Any help is appreciated. Cheers