计算:(-2y-3x)(3x-2y)= ( ); (-2y2-3x)(3x-2y2)=( )
4y2-9x2 ;4y4-9x2
Tom, together with his sister,___going to visit Shanghai next month. [ ]
A.is
B.are
C.will
D.can
转关运输中,直转方式转关的期限为自申报之日起( )天内。
A.14 B.5 C.30 D.15