出售某种文具盒，若每个获利x元，一天可售出（6﹣x）个，则当x=（ ）元时，一天出售该种文具盒的总利润y最大．
3
Theme park owners _____ their profit ____ charging admission fees, ______ new brand athletic
equipment and selling souvenirs.[ ]
A. have; from; advertising for
B. make; by; advertising
C. gain; with; advertising
D. benefit; through; advertising for
进入3岁后，儿童( )。
A．个性萌芽
B．个性尚未发生
C．出现较稳定的个性特征
D．个性的独特性迅速发展，而稳定性发展缓慢
