Activity 12-2: Birth Weights 12-2, 14-9, 14-17 Birth weights of babies in the United States can be modeled by a normal distribution with mean 3300 grams (about 7.3 pounds) and standard deviation 570 grams (about 1.3 pounds Babies weighing less than 2500 grams (about 5.5 pounds) are considered to be of low birth weight. a. A graph of this normal distribution appears next. Shade in the region whose area corresponds to the probability that a randomly selected baby will have a low birth weight. 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 Birth Weight (grams) b. Based on this shaded region (remembering that the total area under the normal curve is 1), make an educated guess as to the proportion of babies born having a low birth weight. c. Calculate the z-score for a birth weight of 2500 grams.d. Look up this z-score in Table II to determine the proportion of babies born having a low birth weight. In other words, find Pr(Z