Please help 49 points Part A: The Sun produces 3.9 ⋅ 1033 ergs of radiant energy per second. How many ergs of radiant energy does the Sun produce in 2.45 ⋅ 105 seconds? Express your answer in scientific notation and show your work. (5 points)

Part B: Which is the more reasonable measurement of the distance between the tracks on a DVD:
7.4 ⋅ 10−4 mm or 7.4 ⋅ 104 mm? Justify your answer. (5 points)