To get better at 12's:
Write down on your paper your 1's facts in column skip 5 and 11 going to 14 (a vertical line - line that goes up and down). To the right of that column, write your two's facts 0 to 8 and repeat again. Then you will have your 12's! Should look as follows
12's:
0 0 = 12 x0
1 2 = 12 x1
2 4 = 12 x2
3 6 = 12 x3
4 8 = 12 x4
6 0 = 12 x5
7 2 = 12 x6
8 4 = 12 x7
9 6 = 12 x8
10 8 = 12 x9
12 0 = 12 x10
13 2 = 12 x 11
14 4 = 12 x 12
M = 90 kg,
On Mars: g = 3.71 m/s²
Weight = m · g = 90 kg · 3.71 m/s² = 333.9 N
1 N = 0.2248 lbf
333.9 · 0.2248 = 75.06072 lbf ≈ 75 lbf
