valentina is trying to decide whether to join her school's swim team. during the summer, the team practices 4 days per week. each of those days, they practice for 3 hours in the morning and practice again in the afternoon. they practice for a total of 20 hours each week. which equation can you use to find h, the length of each afternoon practice in hours? how long is each afternoon practice? write your answer as a whole number or a simplified fraction.