In order to estimate the difference between the average mortgages in the southern and the northern states of the United States, the following information was gathered.South NorthSample Size 40 45Sample Mean (in $1,000) $170 $175Sample Standard Deviation (in $1,000) $5 $7a. Compute the degrees of freedom for the t distribution.b. Develop an interval estimate for the difference between the average of the mortgages in the South and North. Let Alpha = 0.03.