路堤是指全部用岩石或土填筑而成的路基，路床以下的路堤分上、下两层，路面底面以下（）范围的填土部分为上路堤，上路堤以下的填方部分为下路堤。 ["30-150cm","80-150cm","30-80cm"]
多细胞生物无论体型大小，其体细胞的体积都不能太大。这种现象的合理解释是（）。 ["大体积细胞的内部代谢速度过慢","大体积细胞难以分裂","体积大而表面积相对小的细胞不利于生存","体积\/表面积之比调控细胞分裂"]
Gear-type flexible couplings are often used in diesel engine drive trains because they（） ["require no lubrication under normal operating conditions","compensate for gross misalignment in the drive train","are able to transmit high torque ,even where slight misalignment exists","will rapidly disconnect the engine from the line shaft"]
当今国际援助形式发生了变化，其中比重下降的援助形式是（）。 ["A.项目援助","B.方案援助","C.技术援助","D.债务减免"]
Keel coolers fouled with marine growth, will result in （） ["higher raw water temperatures","higher jacket water temperatures","a malfunctioning thermostat","higher fuel temperature"]
什么样的眼镜才算合适的眼镜？
