关于运动和力,说法不正确的是( ) A.物体速度为零时,合外力一定为零 B.物体 发布时间:2017-04-14 11:43 │ 来源:www.tikuol.com 题型:多选题 问题: 关于运动和力,说法不正确的是( )A.物体速度为零时,合外力一定为零B.物体作直线运动,合外力一定是恒力C.物体作曲线运动,合外力一定是变力D.物体作匀速运动,合外力一定为零
题型:多选题 用英文数字填空1. four + eight = _________2. seven + eight= _________3. thirteen + seven = _________4. fourteen + sixteen = _________5. seventy - fourteen = _________6. eighty - sixteen = _________7. sixty - thirteen = _________8. eighty - forty= _________9. forty-eight - twelve= _________10. ninety + five = _________ 查看答案
题型:多选题 The WWNWS is a coordinated global service for the broadcast by radio of vital information on()to marine navigation.A.ship’s movementB.safetyC.ship’s managementD.hazards 查看答案