Welcome to our RU-vid channel dedicated to providing information and resources on child education, with the goal of helping parents and educators better understand and implement effective teaching techniques and methods for children of all ages.
For #2, the number of trailing 0 is simply the power of 5 in the factorial, so 20! has 4 trailing 0 (from 5, 10, 15, 20) and 15! has three trailing zero (from 5,10,15). It becomes trickier when number get larger because 25 would have two powers of 5 and so on.
加州大学，在录取学生时是不看AP成绩的，只有在新生入学以后，AP成绩才起作用（至少2021年是这样）。所以，AP成绩是1分，2分又如何？只是在大学里要重新学而已。UC 网站："Although the College Board reports all AP test results to us, students should be aware AP test scores lower than 3 will not adversely affect their chances for admission."
