(1)原式=3×3-1
=3-1
=2;
(2)原式=(1-3)2+12×43
=1-23+(3)2+23
=4.
Jenny hopes that Mr.Smith will suggest a good way to have her written English _______ in a short period.
A.improved
B.improving
C.to improve
D.improve
如图是粗盐提纯的主要操作,其中正确的是( )
A.称量5.0g粗盐
B.量取10mL水
C.过滤
D.蒸发滤液