There is a test that is commonly done to determine if data in a sample is derived from a normal distribution. In this test, the null hypothesis is that the variable is normally distributed. A test statistic of 0 would indicate perfect normality in the sample. Values far from 0 indicate a lack of normality. The equation for this test statistic is given as follows: ;=E(2+1(_3)2) 6 4- 12'?- (x: .2233 1:1 Where :1) is dened as: n (amm2) Mn: 1 n _ andybisdefinedas: 1 n _ 2 (EE[=1(xi_x)2) a] On which descriptive statistics ofa distribution are d) and 7,0 based? Hint: they are often described as drerent \"moments\" of the distribution. For the following parts of the question, use jtest data [I will provide this in the comments}: b] Compute)ll c] Assume this statistic is distributed as a X2 with two degrees of freedom. Determine if the null hypothesis of normality is to be rejected with 95% confidence. d] Explain why we use critical values from a distribution with two degrees of freedom when considering] , regardless of the number of observations