Nomor 4 dan 5 dong please caranyaa.... Thanks banget

Mt = Mo (1 + i)ⁿ
842956,80 = 600000 (1 + 0,12)ⁿ
8,429×10^5 = 6×10^5 (1,12)ⁿ
log (8,429×10^5) = log (6×10^5 (1,12)ⁿ)
log 8,429 + 5 = log 6 + 5 + n log 1,12
0,9257 = 0,7782 + 0,00492 n
0,1476 = 0,00492 n
n = 3