Question: An experimenter measures the separate masses M and m of a car and trailer. He gives his results in the standard form Mme, ± 8Al and tube. ± Sm. What would be his best estimate for the total mass M + m? By considering the largest and smallest probable values of the total mass, show that his uncertainty in the total mass is just the sum of 8M and 8m. State your arguments clearly; don't just write down the answer. (This problem provides another example of error propagation: The uncertainties in the measured numbers, M and in, propagate to cause an uncertainty in the sum M + tn.)