Problem $1$ of $2(190$ points$)($approximate required time: $25$ minutes$)$

Spectral reflectivity of an opaque surface is given below. This surface is at $400C$ and is located in a room, which is at

$100C.$ The surface has an area of $2\mathrm{.}5m^2.$ Neglecting the convection effects, find the following:

a$)$ Total emissivity of the surface

b$)$ The radiation that emits from the surface $[$W$]$

Note: With the current information, if it is possible to find the desired quantities, find them. If it is not

possible, mention exactly why and what other information you would need to be able to find them. If

possible, make the necessary assumptions and proceed with your calculations to find them.