Experienced baseball fielders can tell
how far a ball is going to travel just by listening to the crack of the bat. If
they didn’t, they wouldn’t stand a chance of catching it, claims a physicist in
New York. "When a baseball is hit straight at an outfielder, he cannot quickly judge the angle of the scent and the distance the ball will travel," says Robert Adair, a physicist at Yale University. If he relied purely upon visual information, the fielder would have to wait for about one-and-a-half seconds before he could tell accurately if the pitcher hit the ball long or short. By this time the ball may have travelled too far for him to reach it in time. To stand a fighting chance of catching it, according to Adair, fielders must listen to the sound the ball hitting the bat to judge how far it will travel. There is anecdotal A. a long ball B. a short ball C. a good ball D. a mishit ball [单选题]《行规》第50条:同一作业区内有( )及其以上机车同时作业时,必须加强联控,车站值班员应主动与调车指挥人、司机联系确定放行顺序,放行顺序发生变化时必须联系彻底,原则上应先放行无调车信号机阻挡的机车,机车车辆未越过调车信号机,车站不得办理与该调车信号机防护进路有关的其他调车进路。
A.三台 B.多台 C.两台 D.一台 [多选题]根据南方电网公司《10kV及以下电力客户受电工程中间检查和竣工检验工作规范》的规定,以下哪些资料是竣工检验前需要检查的:
A.施工、试验单位委托书 B.施工及试验单位资质证明 C.施工单位工程施工记录、自检报告 D.建设单位(监理单位)工程验收报告 E.电气设备交接试验报告 F.成套设备的型式试验报告 [多项选择]下列哪些作品表达了沈从文对现代都市文明的嘲讽与批判?()
A. 《绅士的太太》 B. 《大小阮》 C. 《来客》 D. 《有学问的人》 E. 《烟斗》 [单选题] 地质年代的中生代包括()。
A. 第四纪和古近纪、新近纪 B. 古近纪、新近纪和白垩纪 C. 白垩纪、侏罗纪和三叠纪 D. 二叠纪和石炭纪 [多项选择]人民检察院提起附带民事诉讼时,出席法庭的检察员的身份是( )。
A. 公诉人 B. 附带民事诉讼的原告人 C. 审判监督者 D. 遭受物质损失单位的法定代表人 [单选题]四磨汤的功用是
A.行气降逆,宽胸散结 B.疏肝泄热,活血止痛 C.疏肝解郁,行气止痛 D.通阳散结,行气祛痰 [多选题]雨淋系统由( )组成
A.闭式喷头 B.雨淋阀启动装置 C.雨淋阀组 D.管道 [单选题]500m长钢轨普通平车运输时,各车辆间( )使用车钩缓冲停止器。
A.不得 B.必须 C.可以 D.由托运人确定是否 [单项选择]The example of Arpad Pusztai is used to illustrate ______.
A. public ignorance of the potential risks in GE food B. the role of TV in publicizing scientific knowledge C. the importance of scientific findings to scientific research D. the threat faced by independent science [填空题]技师、高级技师在完成本职工作的同时,应刻苦钻研专业技术,积极带徒传授技艺,担任兼职( ),指导岗位练兵,及时纠正和制止违反操作技术规程、生产工艺和安全操作的行为
[简答题]北方高科技有限公司,成功地生产和销售两种打印机,假设该公司两种产品的财务和成本数据如下:
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