标题: prep一云里雾里数学题 求指导 [打印本页] 作者: adamilan 时间: 2012-4-16 17:45 标题: prep一云里雾里数学题 求指导 the rate of a certain chemical reaction is directly proportional to the square of the concerntration of the chemical A present and inversly proportional to the concerntration of the chemical B present. If the concerntration of the chemical B is increased by100%， which of the following is closet to the percentage change in the concerntration of chemical A required to keep the reaction rate unchanged?
A 100% decrease B 50% decrease C 40% decrease D 40% increase E 50% increase
