性成熟期的生理特点是()
A.生殖器为幼稚型
B. * * 开始发育
C.月经初潮
D.生育活动最旺盛
E.自主神经功能紊乱
参考答案:D
用3g块状大理石与30mL3mol/L盐酸反应制取CO2气体,若要增大反应速率,可采取的措施是[ ]
①再加入30mL3mol/L盐酸 ②改用30mL6mol/L盐酸
③改用3g粉末状大理石 ④适当升高温度
A.①②④
B.②③④
C.①③④
D.①②③
---You just think of yourself! You kept us waiting for you for over two hours.
---I’m sorry that you _____________think so.
A.would
B.should
C.could
D.might