水运工程混凝土和砂浆材料用量定额中规定泵送混凝土和水下灌注混凝土坍落度超出设计坍落度范围之外,每增减1cm,水泥用量相应增减()。 ["1%","1.5%","2%","2.5%"]
微孢子虫病的主要传播途径是() ["经食物传播","经水传播","虫媒传播","接触传播","空气飞沫传播"]
轻粉的功效是() ["杀虫止血","杀虫截疟","杀虫逐水","杀虫止泻","杀虫补火"]
背景
雷尼替丁的主要作用是()。 ["中和胃酸","促进胃排空","抑制胃酸分泌","黏膜保护作用","阻断胃泌素受体"]
批量小、工序时间短时,可以采用();批量大、工序时间长时,则宜采用平行移动或()。