A:﹣3
B:3
C:13
D:﹣ 13
根据问题选择正确的回答
— What's this? —____;
— How many girs? —____;
— What's your name? —____;
— Is it a dog? —____;
— Where's the book? —____。
单项式﹣ 5x2y6的系数是____ ,次数是____ .
Xi Jinping is about sixty y____ old now.