— Is it your coat ?
— ________. It's her coat. ( )
A:Yes, it is.
B:No, it is
C:No, it isn't.
jiān jiǎ
pīn bó
kū wěi
lún fān
duàn liàn
yī lài
____
在以x为自变量、y为函数的关系式y=2πx中,常量为( )