A Data Set with 7 Observations Yielded the Following $\sum x$

Essay

A data set with 7 observations yielded the following.Use the simple linear regression model where y is the dependent variable and x is the independent variable. $\sum x$ = 21.57 $\sum X ^ { 2 }$ = 68.31 $\sum Y ^ { 2 }$ = 188.9 $\sum Y ^ { 2 }$ = 5,140.23 $\sum X Y$ = 590.83
SSE = 1.06
-Determine the 95% confidence interval for the average value of y when x = 3.25.