It is said that pandas ______ in our country year by year.
A:are being disappeared
B:are disappearing
C:will be disappeared
D:will disappear
①若a= 32 ,则函数f(x)的值域为____;
②若f(x)在R上是增函数,则a的取值范围是____.
某同学利用下面的三幅历史图片开展研究性学习,研究内容应围绕( )