Calculate spectral flux density (hint: it should have erg s1 cm2 Hz1 units in cgs units) at the Earth from a sphere with radius 10 km located at a distance of 0.2 kpc and radiating as a blackbody with temperature kT = 2 keV. Convert your expression for spectral flux density to keV cm2 s 1 keV1 units. Plot this expression as a function of energy in the 0.0550 keV range using logarithmic scales for the x and y axes of your plot. Please use your computer for plotting