题目

单词拼写： 76. Light , heat, and electricity are different forms of e____________. 77. Eating more vegetable and less fat will greatly b___________ your health. 78. The a_________ size for British schools is about 29 students in each class. 79. He i__________ the key into the lock but fond he couldn’t turn it. 80 . These plants can’t s_____________ without enough water and sunshine. 81. Of all the _______________(大陆),  Asia is the largest one. 82. Many friends were invited to Mary's birthday party, Jack____________(包括). 83. It is a bad habit to be ______________ (有瘾) to9．四个完全相同的弹簧秤，外壳通过绳子分别与四个完全相同的物体相连，挂钩一端施加沿轴线方向的恒力F，以下四种情况中关于弹簧秤读数的说法正确的是（　　）A．如果图甲中的物体静止在水平地面上，那么弹簧秤的读数可能小于FB．如果图乙中的物体静止在斜面上，那么弹簧秤的读数一定等于FC．如果图丙中的物体静止在粗糙水平地面上，那么弹簧秤的读数一定等于FD．如果已知图丁中水平地面光滑，则由于物体的质量未知无法判定弹簧秤的读数与F的大小关系