1H
+1
2He
0
3Li
4Be
+2
5B
+3
6C
+4﹣4
7N
+5﹣3
8O
﹣2
9F
﹣1
10Ne
11Na
12Mg
13Al
14Si
﹣4
15P
16S
+6﹣2
17Cl
18Ar
请分析信息并回答下列问题:
如图,△ABC中,∠A=50°,O是BC的中点,以O为圆心,OB长为半径画弧,分别交AB,AC于点D,E,连接OD,OE,测量∠DOE的度数是( )
甲、乙两个容器中盛有相同质量的同种液体,两个容器底受到液体的压力分别为F甲、F乙,受到的压强分别为p甲、p乙,则它们的大小关系为F甲____F乙,p甲____p乙.
Last week I met my old friend Li Ming by accident but I forgot _______ him for his telephone number.