问题
选择题
— Could you ______ me your bike please?
— Sorry , I'll use it. You can _____ Jack's. [ ]
A. borrow, lend
B. borrow, lend
C. lend, borrow
答案
答案：C
搜题请搜索小程序“爱下问搜题”
— Could you ______ me your bike please?
— Sorry , I'll use it. You can _____ Jack's. [ ]
A. borrow, lend
B. borrow, lend
C. lend, borrow
答案：C
是不稳定的，能自发地发生衰变。
应方程
。
，共经过 次
衰变， 次
衰变。