2. A statistician is working on the amount of funding that companies obtain on a crwod- sourcing website and has developed the following model. She used 26 companies to obtain the model y = bo + b121 + 6272 + 63X3 + b4X4 + 650'5 y = 964.8 + 700.2x1 + 317.5x2 - 200.2x3 + 15.3x4 + 17.125 The standard errors are: Sbi = 12. Sbo = 22.5 Sba = 101.8 SbA = 45.3 Sbs = 2.3 . y: the amount of funding obtained by a company in 1000 dollars . x1: the average annual salary of the founders . 72: the number of employees the startup hired . x3: a dummy vaiable that is 1 when the company's field is information technology and 0 otherwise . x4: the age of the company . x5 is a dummy variable taking value 1 if the founders had previous failures and 0 otherwise (a) Interpret the estimated coefficients bo = 964.8 and b3 = -200.2 (10 pts) (b) Test, at the 2% level, the null hypothesis that the true coefficient on the dummy variable 25 is 0 against the alternative that it is not 0. (10 pts) (c) Find and interpret a 99.8% confidence interval for the parameter B4. (10 pts) (d) If for the model, SSR=18147.5 (Regression Sum of Squares) and SSE = 17136.5 (Residual Sum of Squares), test the hypothesis that all the coefficients of the model are 0 (test overal significance of the model) using a = 5%. (10 pts)