3-12. write each answer with a reasonable number of figures. find the absolute uncertainty and percent relative uncertainty for each answer. (a) [12.41 (Β±0.09) + 4.16 (Β±0.01)] x 7.068 2 (Β±0.000 4) =? (b) [3.26 (Β±0.10) x 8.47 (Β±0.05)] - 0.18 (Β±0.06) =? (c) 6.843 (Β±0.008) x 104 + [2.09 (Β±0.04)- 1.63 (Β±0.01)] =?