【单选题】5 Mark suggests that they _____.
A.
eat their picnic while travelling along the river
B.
move over to the bank and stop for a while
C.
eat their picnic in about ten minutes
D.
move over to the bank and eat their picnic
【简答题】Marksuggests that they _____.A. (a) eat their picnic while travelling along the river B. (b) move over to the bank and stop for a while C. (c) eat their picnic in about ten minutes D. (d) move over to...
【单选题】Mark suggests that he punt for _____.
【简答题】51系列单片机具有几个中断源?其中哪些中断源可以被定义为高优先级中断,如何定义?
【简答题】某市对话费作了调整,原市话费为每3分钟0.2元(不足3分钟按3分钟计算).调整后,前3分钟为0.2元,以后每分钟加收0.1元(不足1分钟按1分钟计算).设通话时间x分钟时,调整前的话费为y 1 元,调整后的话费为y 2 元. (1)填写下表,并指出x取何值时,y 1 ≤y 2 ; x 4 4.2 5.8 6.3 7.1 11 y 1 y 2 (2)当x=11时,请你设计三种通话方案(可以分几次拨打...
【单选题】设信号的波特率为500Baud,采用复合调制技术,由4种幅度和8种相伴组成16种码元,则食道的数据率为:
【单选题】设信号的波特率为500Baud,采用幅度-相位复合调制技术,由4种幅度和8种相位组成16种码元,则信道的数据速率为()b/s。
【单选题】急性肾功能衰竭可分为肾前性、肾性和肾后性三类,引起肾后性的常见原因有()
【简答题】椭圆C的中心在坐标原点O,焦点在y轴上,离心率为 2 2 ,以短轴的一个端点与两焦点为顶点的三角形的面积为 1 2 . (1)求椭圆C的方程; (2)若过点P(0,m)存在直线l与椭圆C交于相异两点A,B,满足: AP =λ PB 且 OA +λ OB =4 OP ,求常数λ的值和实数m的取值范围.