既然你已决定做这件事，就应该把它做好。

直线y=kx+b的图象如图所示，则（   ）

    Last year, some groups of students in their community (社区) made a survey about "How do people spend their free time?" The following diagrams show some results of it:
Diagram (1): Hours for people of different ages who surf the Internet in a week.

Diagram (2): Different days people go to the library. (library attendance)

Diagram (3): Different programs people like.

根据上面三个图表内容，选择正确答案。

如图，已知以直角梯形ABCD的腰CD为直径的半圆O与梯形上底AD、下底BC以及腰AB均相切，切点分别是D，C，E．若半圆O的半径为2，梯形的腰AB为5，则该梯形的周长是 ____。