99-(23+39)=____
7×4+15=____
24+40÷8=____
(6+57)÷9=____
8×(69-60)=____
16-7=____ 14-8=____ 10-8=____
11-8=____ 13-7=____ 12-8=____
如图为人体消化系统示意图,请据图作答.