\(12^8.9^{12}=\left(2^2.3\right)^8.\left(3^2\right)^{12}=2^{16}.3^8.3^{24}=2^{16}.\left(3^2\right)^{16}=2^{16}.9^{16}\left(2.9\right)^{16}=18^{16}\)
a, 128.912
=(22.3)8.(32)12
=216.38.324
=216.38.316.38
=(2.3)16.(32)8
=616.316
=(6.3)16
=1816
7520
=(52.3)20
=540.320
=530.510.(32)10
=530.510.910
=530.(5.9)10
=530.4510