  
 Exa-3.5(a)   
The wavelength at which emits maximum radiation is 9.89 um.
 
 Exa-3.5(b)   
The temperature of the object must be raised to 4458 K.
 
 Exa-3.5(c)   
Thus the thermal radiation at higher temperature is 5.36e+004 times the room (lower) tempertaure.
 