530. Вычислите 1) 21-(5-8)= 2) 3,7- (4 - 5,3)= 3)1/6 - ( 5/12 - 7/12) = 4)-13-(20-32)= 5)-4,5-(7-9.5)= 6)-5/8-(5/8-1)= 7)-18-(9-5)= 8)-0,25-(3-2,25)= 9) -2/9 - ( 1 - 8/9 )=