库仑分析的先决条件是100％电流效率，若阳极或阴极有干扰物质产生时，可采用（）或将产生干扰物质的电极置于套管内隔开方法。
参考答案：盐桥
松鼠妈妈采松子，晴天每天可以采20个，雨天每天只能采12个．它一连采了几天共采了112个松子，平均每天采14个．这几天中有______个雨天．
It's reported that women with demanding jobs are almost _____ to suffer a heart attack.[ ]
A. as likely twice
B. likely twice as
C. twice as likely
D. twice likely as
