x225y2=(x5y)2=-x5y,
x、y为异号,即xy<0.
故答案为:xy<0.
29.It was _____he said ____disappointed me.
A.What; that
B.that; that
C.what; what
D.that;what
《职业病防治法》规定,用人单位应当为劳动者创造符合我国职业卫生标准和卫生要求的工作环境和条件,并采取措施保障劳动者( )。
A.获得职业卫生保护
B.获得职业卫生资格
C.获得职业卫生经费
D.获得职业卫生目的