Answer:
Part A: The answer is C
Part B: Joanna worked 36 hours last week.
Explanation:
Part A: The answer is C because the other ones wouldn't make sense. For example, in choice A it says to add h to 12, but you wouldn't know what h is. On choice B it wants you to multiply what she earned the whole week to how many hours she worked. That would only work if you divided h by 432, but you still would not know what the value of h is. The last choice has nothing to do with the problem. Therefore, choice C is the best one.
Part B: You divide 432 by 12 and get 36 hours.