hello i need help with these two statistic questions thank you

question 7 for C only

c) repeat part (b) for samples of size 450 find the mean and the standard deviation so two parts pleas thanks

Aresearcher focusing on birth weights of babies found that the mean birth weight is 33\" grams (? pounds, 6.9 ounces) with a standard deviation of 532 grams. Complete parts (a) through (c) below. a. Identity the population and variable. Choose the correct population below. The number of babies born the year the research was performed The group of all of the babies whose recorded weights were examined The group of researchers The group of all babies ever born Choose the correct variable below. The accuracy of the measurements of baby birth weights The number of births per ca pita V The weights of the babies at birth The number of babies that were born b. For samples of size 22 5, find the mean \"i and standard deviation oi of all possible sample mean weights. \"i = 3371 {Type an integer or a decimal. Do not round.) a; = 38.8 (Round to two decimal places as needed.) 1:. Repeat part (b) for samples of size 450. \"i = 2?.44 (Type an integer or a decimal. Do not round.) Assume that females have pulse rates that are normally distributed with a mean of p = 72.0 beats per minute and a standard deviation of o = 12.5 beats per minute. Complete parts (a) through (c) below. . . . a. If 1 adult female is randomly selected, find the probability that her pulse rate is less than 79 beats per minute. The probability is 0.7123 . (Round to four decimal places as needed.) b. If 4 adult females are randomly selected, find the probability that they have pulse rates with a mean less than 79 beats per minute. The probability is (Round to four decimal places as needed.)