(2^3)^4= (2^3)•(2^3)•(2^3)•(2^3) = (2•2•2)•(2•2•2)•(2•2•2)•(2•2•2)
(4^5)^2= (4^5)•(4^5) = (4•4•4•4•4)•(4•4•4•4•4)
(x^7)^3= (x^7)•(x^7)•(x^7) = (x•x•x•x•x•x•x)•(x•x•x•x•x•x•x)•(x•x•x•x•x•x•x)
(3•5)^3= (3•5)•(3•5)•(3•5)•(3•5) = (3•3•3•3)•(5•5•5•5)
(xy)^3= (xy)•(xy)•(xy)•(xy) = (xxxx)•(yyyy)
hope this helps :)