5. A bank has a number of coins which equals $2.9 in total. There are only 2 types of coins, $0.25 each and $0.05 each. What is the remainder if the number of $0.05 coins can be divided by 5? (forgot the answers)
请问这黄色highlight部分什么意思啊,什么的remainder?
两个圆,圆心被一条直线连起来,a, b 分别在2个圆上。如果两个圆tangible,问a, b的最大距离是多少?这个tangible是指外切还是内切还是都要考虑啊,