3. Assume we have 99 weekly data points on the returns to a particular stock expressed in percentage terms and defined as x. The following quantities are computed from the data: 99 99 90 > xi = 17.74971; Exi = 533.9367; E(x - = 139.1049; E Xi - = 8310.4263. i-1 i-1 i-1 i-1 (a) Use these quantities to determine whether the data are skewed. (b ) Use these quantities to determine the kurtosis value of the data. (c) Use these quantities to perform a test for normality using a 5% significance level