题目

71. The speech contest will be held next Friday. I must make full ___________（准备）for it. 72. He doesn’t a______________ of me leaving here, but I won’t change my mind. 73. Climbing Mount Everest is a c______________ task to all mountain climbers. 74. Have you anything to say in __________(解释）of your rudeness? 75. We got into an a________________ about whether to go by sea or by air and then asked Mr. Li for advice. 76. Her father f___________ her to marry the poor boy, which made her very sad. 77. While the TV is on, it’s hard for me to c_____________ my mind on the h为了寻找反物质或暗物质，中、俄、美等十几国联合研制并于1998年用航天飞机发射了“a一磁谱仪”，其核心是我国研制的永磁体，其质量达2t．这个永磁体的主要材料是铁质，外形是底面积11000cm2、高80cm的圆柱体．那么它的平均密度为2.3×1032.3×103kg/m3，估计它是否是实心的不是不是（选填“是”或“不是”）．（ρ铁=7.9×103kg/m3）