$A$ student constructed a box-type solar cooker. He found that it is not working efficiently. What could this be due to? Give any four possible mistakes in the construction and operation of the solar cooker. What maximum temperature can ordinarily be reached inside a solar cooker?

(N/A) The reasons for the inefficient working of the solar cooker could be as follows:
$(i)$ The inner surface of the box might not have been painted black to absorb maximum solar radiation.
$(ii)$ The box might not have been properly insulated,leading to heat loss.
$(iii)$ The reflector might not be positioned at the correct angle to direct sunlight into the box.
$(iv)$ The glass cover might be too thin or not airtight,allowing heat to escape.
Ordinarily,the maximum temperature that can be reached inside a box-type solar cooker ranges between $100^{\circ}C$ and $140^{\circ}C$.