改革开放以来，中国净进口粮食占国内粮食生产的比重呈减少趋势，1978～1984年为3

广义信息资源包括( )

A．信息、物资、货币

B．信息、信息生产者、物资

C．信息技术、信息生产者、货币

D．信息内容、信息技术与设施、信息人员

男孩，出生后3天发现有明显呼吸急促，不吃奶，发绀，体检发现心脏扩大，无明显杂音。首先考虑()

A．法洛四联症

B．动脉导管未闭

C．肺动脉狭窄

D．房间隔缺损

E．完全性大动脉转位

加油和CNG加气合建站中的储罐容积符合（）条件时，该合建站的等级为一级。

A.油品储罐总容积90m3<120m³

B.常规CNG加气站储气设施总容积<24m³

C.油品储罐总容积≥90m³

D.油品储罐总容积<60m³

E.常规CNG加气站储气设施总容积<12m³

在国际期货市场上，( )是目前占据主导地位的期货品种。

A．金属期货
B．金融期货
C．农产品期货
D．能源期货

Microwave communication uses high-frequency (71) waves that travel in straightlines throughthe air. Because the waves cannot (72) with the curvature of the earth, they can be (73) only over short distance. Thus, microwave is a good (74) for sendingdata between buildings ina city or on a large college campus. For longer distances, the wavesmust be relayed by means of"dishes" or (75) . These can be installed on towers, highbuildings, and mountain tops.

A．material

B．equipment

C．medium

D．channel