Suppose that we want to compare the waiting times between repairs of two systems (in days), S] and 5'2 . Here are histograms of the waiting times: Which of the following options is a reasonable conclusion from these histograms? O the populations are normal with equal variances 0 only one of the populations is normal 0 none of the preceding 0 the populations are not normal 0 the populations are normal with unequal variances