-- That T-shirt with Yao Ming's picture on it ____ belong to David. He admires him a lot.
-- No, it _____ be his. He hates black color.
A:can; can't
B:may; needn't
C:must; mustn't
D:must, can't
如图所示,船从A处开出后沿直线AB到达对岸,若AB与河岸成37°角,水流速度为4m/s,则船从A点开出相对静水的最小速度为( )
有人说,成功需要朋友,而取得巨大的成功更需要敌人。该观点的合理性在于( )
①联系是事物存在和发展的条件
②矛盾双方在一定条件下相互转化
③克服困难的信念是成功的决定因素
④同一是差别和对立的前提。