1. -0.5÷7/8×(-5/4)2. (-7)÷(-3/2)÷(-7/5)3. 3又1/3÷(-2又1/3)÷(1又1/5)4. 1÷【(-1)÷4/5】5. (-2/3)×8/27×(-1.5)÷(-16/9)6. (-36)÷(1又1/2)×(-2/3)7. (-2/3)×(-8/5)÷(-0.25)这是几道计算题,要有过程,各位大侠帮个忙呀~~~~~急呀~~~~~~~