【简答题】Some policymakers believe that bio-fuel could help to save American farm, besides relieving pressure on______.
【单选题】To help the sick people in the hospital is _____ for me .
【单选题】能代替水准测量建立高程控制的高程测量方法是( )。
【单选题】需求价格弹性是指()变动百分率和()变动百分率的比值。
【单选题】Good _________ habits help me get good grades.