Statistics please assist

The following sums were obtained from a sample of 6 observations on x and y. Ex = 450, 2y = 267, ny = 17,950, 2x2 = 35,500 The least-squares regression equation is Select one: y = 144.5 + 75x y = 1.186 + 133.450x y = 45.325 0.011x y= 133.450 - 1.186x Which of the following is an example of a discrete random variable? Select one: The number of cows on a randomly selected cattle ranch in Texas The distance a randomly selected car will drive with a full tank of gas The amount of rain that falls over a 24-hour period in a randomly selected rainforest The weight of a randomly selected package at the post ofce Which of the following is a measure of dispersion? Select one: O The mode O The mean O The Pearsonian coefficient of skewness O The standard deviation