a) 816:416=(2.4)16:416=216.416:416=216
b) 276:92=\(\left(3^3\right)^6\):\(\left(3^2\right)^2\)=318:34=314
c) (a-b)5:(b-a)3=(a-b)3:\(\left(\left(-1\right)^3\left(a-b\right)^3\right)\)=(a-b)5:(a-b)3:(-1)3=-(a-b)2
d) (a-b)7:(b-a)4=(a-b)7:\(\left(\left(-1\right)^4\left(a-b\right)^4\right)\)=(a-b)7:(a-b)4=(a-b)3