上体前屈时腹痛明显、直立位时减轻，提示何种疾病
A．十二指肠淤滞症
B．胰体癌
C．反流性食管炎
D．胃粘膜脱垂
E．胃溃疡
参考答案：C
After staying in room for weeks, the lady was advised to go to the outside world to ______ her confidence as well as health.
A．take up
B．make up
C．carry up
D．pick up
喷泉广场上组合喷泉的喷嘴竖下直向上。某一喷嘴喷出水的流量Q＝300 L/min，水的流速v0＝20 m/s。不计空气阻力，g=10m/s2 。则处于空中的水的体积是 （ ）
A．5 L
B．20 L
C．10 L
D．40 L
