Can someone help with these 2 questions?

Although changes result from business transactions, the equality of the fundamental bookkeeping equation must remain. t/f

Students are given 3 minutes for each multiple-choice question and 5 minutes for each free-response question on a test. there are 15 questions on the test, and students are given 51 minutes to take it.how many multiple-choice questions are on the test?

How can constraints be used to model a real-world situation?