b$)(20$ marks$)$

A glass$-$door firescreen, used to reduce exfiltration of room air through the chimney, has a height of $0\mathrm{.}71$ m and a width of $1\mathrm{.}02$ m and reaches a temperature of $175C$ If the room temperature is $23C,$ using an illustrative diagram, estimate the convection heat transfer from the fire place to the room Show all the workings.