【判断题】进气门早开,增大了进气行程开始时气门的开启高度,增加了进气阻力,增加进气量。进气门晚关,延长了进气时间,在大气压和气体惯性力的作用下,增加进气量。
【简答题】阅读下列文章,回答 31~35 题 归帆 我看过太湖上的归帆,也看过东海上的归帆。 夕阳把水面映得通红,把天空也染成万道彩霞。一会儿,黄昏的纱幕就轻轻地落在水面上。就在这当儿,水天相接处出现了一只帆影,接着又是一只……不多久,整个船队都出现了,它们散散落落地驶回港口,仿佛一队出征的战士,唱着凯歌整队回营,带着满舱的战利品。 但这只是在岸上看到的远处的景象,等到这些船只快靠码头,船老大准备向岸上抛缆...
【单选题】In America, many people waste a lot of food _____ in Africa people haven’t enough to eat.
【判断题】集热器盖板的技术要求:具有高全光(太阳)透射比;红外透射比低;有较高的耐冲击强度;有良好的耐候性(适应各种气候条件);导热系数小,隔热性能好;便于加工。
【单选题】Many people didn't expect that very successful people______.
A.
can succeed in difficult tasks but fail in very simple ones
B.
aren't clear why they succeed in achieving their goals
C.
tend to feel very lonely when they reach their goals
D.
are born with some special ability to do something well