∫20(2x-ex)dx=∫022xdx-∫02exdx=x2|02-ex|02=4-（e2-1）=5-e2，
故答案为5-e2．
保持环境就是保护人类自己。保护环境，人人有责！ [ ]
The water ______ cool when I joined into the pool for morning exercise. [ ]
A. was felt
B. is felt
C. feels
D. felt
