1.
52 = 5 * 10 + 2 = LII
43 = 4 * 10 + 3 = XLIII
436 = 4 * 100 + 3 * 10 + 6 = CDXXXVI
435 = 4 * 100 + 3 * 10 + 5 = CDXXXV
748 = 7 * 100 + 4 * 10 + 8 = DCCXLVIII
1200 =1 * 1000 + 2 * 100 = MCC
2.
3 * 1000 + 2 * 100 + 4 * 10 + 5 = 3245 = MMMCCXLV
7 * 100 + 5 * 10 + 3 = 753 = DCCLIII
200 + 50 + 5 = 255 = CCLV
300 + 80 + 9 = 389 = CCCLXXXIX
3.
XXXIV = 34
XXIX = 29
CLIV = 154
LXXV = 75
MDC = 1600
LIX = 59