A：“跳远助跑”时利用了惯性
B：“引体向上”时手搓镁粉利用了增大摩擦的道理
C：“踢足球”时利用了力使物体运动状态发生改变的道理
D：“仰卧起坐”时利用了大气压的原理
Tom and Jane ___________ a dog (狗) . They like it a lot.
用括号内所给词的适当形式填空。
—The plane is leaving right now, but Jim hasn't arrived yet.—Well, he said he _____here on time.
79×58+29×58 ＝（ ）
