Question $4)$ A $10mm$ thick glass plate having dimensions of $1mx1m,$ is taken out of an oven at $120C$ and suspended vertically to cool. If the ambient temperature is $20C$ and the pressure is $1$atm, find the heat lost by natural convection from the surfaces of the glass plate in one minute. $(25$ Points$)$

Properties of air at $20C,Cp=1,007k\frac{J}{k}gK,=1,8{10}^{-5}N\frac{s}{m^2},k=2,5{10}^{-2}\frac{W}{m}K$

Properties of air at $120C,Cp=1,014k\frac{J}{k}gK,=2,3{10}^{-5}N\frac{s}{m^2},k=3,35{10}^{-2}\frac{W}{m}K$