题目

As is often pointed out, knowledge is a two-edged weapon which can be used ________ for good or evil．        A．similarly   B．properly   C．equally    D．widely 答案：C 解析: 略下列描述属于化学变化的是A.干冰升华B.铁矿石炼铁C.海水蒸发D.电灯发光