重碳酸盐在一定温度下会分解生成()和()沉淀,使硬度消失。
参考答案:碳酸钙CaCO3;氢氧化镁Mg(OH)2
—Who will go to the airport to meet Mary?
—I will. I her several times. I can find her easily.
A.met
B.have met
C.had met
D.will meet
上消化道出血是指()以上的消化道出血。