计算:
(1)-6+π-3.140--13-1
(2)(a3)2•(﹣2ab2)3
(3)-12-3+-340+-123
(4)(﹣a2)3﹣(﹣a3)2+2a5•(﹣a)
0.6:1.8的最简整数比是____:____比值是____