A:b﹣a=n+m
B:a﹣b=n﹣m
C:质子数Y>X
D:核电荷数Y<X
—Yes,it's _______ September 3rd _______ each year.It tells the world that Chinese people love peace and hate wars.Chinese people will never forget the history.
—What's that on your desk, Linlin?
—It's a new travel p____.