19) Suppose the maximum speed of a moped (small motorcycle) is normally distributed with mean value 46.6 km/h and standard deviation 1.75 km/h. Consider randomly selecting a single such moped. What is the probability that maximum speed is at least 47 km/h? a) 0.974x b) 0.409 c) 0.744 d) 0.841 20) The mean height of a soldier in an army is 70 inches. 10% of the soldiers in the army are taller than 72 inches. Assuming that the heights of the soldiers in this army are normally distributed, what is the standard deviation? a) 1.0286 b) 0.72 c) 1.5625 d) 0.70