设集合{x|x²+12$\sqrt{3}$x+83≤0}={x|a≤x≤b}，则b﹣a=____ 

（____）A. There is a school in my village.

（____）B. There is a river on the mountain.

（____）C. There're many animals in the forest.

（____）D. There is a tree behind the building.

（____）E. There is a lake near the house.

在现代生活中越来越突出，成为更为直接的文化传播的是    （    ）