Marco is interviewing classmates for a science project. He needs to have interviewed a total of 30 classmates this week to make sure his findings are accurate. Every interview takes Marco 7.2 minutes to complete. On Wednesday, Marco estimated that he has completed about 45% of his interviews. Part A: About how many classmates was Marco able to interview in the beginning of the week? Part B: Using the information you calculated in Part A, how many more minutes does Marco have left to spend on his project this week?