题目

Welcome every morning with a smile. Let your first hour set the theme of success and positive action that is certain to echo(回响) through your entire day. Today will never happen again. Don’t waste it with a false start or no start at all. You were not born to fail.Starting the day right can give good momentum (动力) for the rest of the day. Having a power morning is a key factor for a fruitful day. Here are some tips on getting the most out of the morning.Wake up early. In theory, there’s no difference in waking up early or late as long as you get the proper amount of sleep. However, 钨是熔点最高的金属，广泛应用于拉制灯丝，有“光明使者”的美誉．我省蕴藏着丰富的钨矿资源冶炼金属钨常用到白钨矿石，其主要成分是钨酸钙(CaWO4)，钨酸钙中钨(W)的化合价为 [　　] A．－6 B．＋4 C．＋6 D．＋7