【单选题】在立式铣床加工较大平面时,一般采用( )
【简答题】加工较大平面时,一般采用( );加工空间曲面、模具型腔时多采用( ) A.立铣刀 B.键槽铣刀 C.面铣刀 D.模具铣刀
【单选题】男性,35岁,发热,胸部持续性钝痛二天,胸痛于仰卧时加剧,用硝酸甘油无效,心音减低,伴舒张期附加音,BP110/80mmHg,下肢水肿,静脉压180mmH 2 O,ECG://ST段抬高,弓背向下,未见Q波。
下列哪项体征不支持大量心包积液()
【单选题】Why do doctors recommend folic acid supplements for pregnant women?
A.
Because folic acid is effective in preventing the death of embryos.
B.
Because the right amount of folic acid helps prevent neural tube defects.
C.
Because a mouse study has shown folic acid causes birth defects in mice.
D.
Because pregnant women eat fewer leafy vegetables than they need.
【单选题】一开始就沾满了实用主义的商业气息的是( )。
【单选题】()是语言表达的前提,建立良好人际关系的基础。