A:or
B:and
C:the
D:so
疑难____ A.nán B.nàn
更____ A.gēng B.gèng换
在“家电下乡”活动中,小明家买了一只WSJ﹣60型号电热壶,其铭牌标志如图所示.现将一满壶20℃的0.5kg的水在额定电压下烧开需时5min,已知外界气压为1标准大气压〔c水=4.2×103J/(kg•℃)〕.求:
型号
WSJ﹣60
额定电压
220V
额定功率
800W
水壶容积
500mL
I'm Lucy. I have a happy family. There are four people in my family. My birthday is on January 1st. It's New Year's Day, too. My family and I will have a big dinner on that day. I have a little brother. He is four years old. His birthday is in winter. It's very cold but we can make a snowman. My mother's birthday is in March. My father's birthday is in March,too. We can plant trees and fly kites.
下图中纵轴表示价格,横轴表示供给量和需求量,D是某商品需求曲线,S是某商品供给曲线。据图可以推断( )
①当某商品价格处于P2时,供过于求,供给者应降低价格
②当某商品价格处于P2时,供不应求,供给者应增加供应
③当某商品价格处于P1时,供过于求,需求者可以压低价格
④当某商品价格处于P1时,供不应求,供给者可以提高价格