Suppose that a polar bear's foot has a luminosity of L=10 watts. What is the bolometric absolute magnitude of the bear's foot? What is the bolometric apparent magnitude of the foot at a luminosity distance of dL=0.5 km? If a bolometer can detect the bear's foot at a maximum luminosity distance of dL=0.5 km, what is the maximum luminosity distance at which it could detect the Sun? What is the maximum luminosity distance at which it could detect a supernova with L=4×109L⊙?