小明和小华在操场上沿直跑道跑步，他们通过的路程和时间关系如图所示，则下列说法正确的是（）

   When it rains, do your shoes get wet? Of course they do! But you can buy these pretty red and white “Umbrella for Shoes”. They keep the rain off wet.
   Who sweeps the floor at your home? Do you do it yourself? Perhaps your mother does it. Well, now you just need a cat. Get a cat and buy these four “Dusters (抹布)for Cats ”.
   You talk too long on the phone, don’t you? Most teenagers do! Save time – buy the “Telephone Dumb–bell (哑铃)”! It weighs five kilos. Then your calls will be less than five minutes.
   Do your friends sometimes come up behind you and make you jump? Do cars come around the corner when you try to cross the road? Well, you can solve that problem with these modern “Forward – backward Glasses.” Look forward with the right eye and back with the left.

同学们一起探究铝、铁、铜三种金属的活动性，小刚同学设计了用铜丝、铁丝、铝丝和稀盐酸，只用一只试管，取一次盐酸的探究方案。请你和他们一起完善下表的探究方案并回答有关问题。