The following are the numbers of sales which a random sample of ten salesmen of industrial chamicals in Area A and a random sample of seven salesmen of industrial chemicals in Area B made over a fixed period of time: Area A: 41 46 60 35 58 65 39 59 52 40 Area B: 35 65 57 48 20 39 36 Assume that the population variance of two events are not equal and unknown. Compute the margin of error using the level of significance a = 0.10