I need help solving (d1)?

Susan Shi owns TestTutor, an educational tutoring center in Greenville, South Carolina. The center offers private tutoring in math, writing, and science. Information about the tutoring sessions is as follows: Math $34 Science $25 10 20 Session price Variable labor costs Variable supplies cost Session length Number of sessions demanded per week Writing $50 30 2 90 minutes 260 2 45 minutes 180 30 minutes 120 Since the company opened five years ago, demand has grown faster than the supply of qualified tutors. Susan currently has enough tutors to provide only 420 hours of tutoring each week. (a 1) Your answer is correct. Calculate the total number of hours demanded per week. (Round answers to 0 decimal places, e.g. 5,275.) Hours needed 135 Math 390 Writing 60 Science 585 Total e Textbook and Media Attempts: 2 of 3 used Using multiple attempts will impact your score. 20% score reduction after attempt 2 (b) Your answer is correct. How should Susan allocate the currently available tutor hours? (Round answers to 0 decimal places, e.g. 5,275.) Hours used Math 135 Writing 225 60 Science e Textbook and Media Attempts: 2 of 3 used Using multiple attempts will impact your score. 20% score reduction after attempt 2 Your Answer Correct Answer (Used) What total contribution margin will Susan earn based on your answer to (b)? $ $ Contribution margin 6,540 (d1) Susan has decided that instead of offering individualized instruction in math and science, she will switch to group sessions. Each math session will accommodate two students, and each science session will accommodate four students. Each student in the group will continue to pay the original session price. All sessions will have a single tutor, but each student will need supplies. Calculate the total hours needed with the group sessions. (Round answers to 2 decimal place, e.g. 15.25.) Hours needed Math Writing Science Total eTextbook and Media