It takes Janet about forty minutes her homework every evening.
15×( 23 + 35 )
13 × 12 + 12 × 23
( 12 ﹣ 16 )× 35 ÷ 15
( 34 + 58 )×32
5÷( 23 + 15 )× 113
48×( 712 +2)÷ 23
I think basketball is _______. I like to watch it.
现有A、B、C三种金属,当把A和B分别放入稀硫酸中时,A溶解并产生氢气,而B不反应;当将B和C分别放进硝酸银溶液时,不一会就发现在B的表面有银析出,而C不反应.由此可知A、B、C这三种金属的活动性由强到弱的顺序是( )