如图,∠1=∠2,PD⊥OA,PE⊥OB,垂足分别为D,E,下列结论错误的是( )
A:PD=PE
B:OD=OE
C:∠DPO=∠EPO
D:PD=OD
优秀
非优秀
合计
甲班
10
50
60
乙班
20
30
80
110
K2≥k
0.100
0.050
0.025
0.010
0.001
k
2.706
3.841
5.024
6.635
10.828
参考公式与临界值表:K2= n(ac−bc)2(a+b)(c+d)(a+c)(b+d) .
—Many people eat _______ meat and _______ vegetables than they did before.
—Yes, that's why they're getting fatter and fatter.
我又发现了一块“绿洲”——小镇文化站有几百册图书。句中破折号的作用是( )