I need some assistance with the following HW assignment. See attached for material. Any help would be much appreciated. This requires some knowledge of SAS programming. I can send tutor the datasets needed to answer these questions.

(60 points) Researchers in toxicology study were interested in evaluating the effects of air pollution on vasoconstriction of small pulmonary arteries in rats. Also, they wanted to know if these health effects differed according to whether the rats had preexisting pulmonary disease. Thus, chronic bronchitis was induced in some of the rats by exposing them to 802 for 6 weeks prior to pollution exposure. All rats were randomized to one of four groups: 0 ltered air, not exposed to 802 o concentrated air particles (CAPS), not exposed to 802 o ltered air, exposed to 802 o concentrated air particles (CAPS), exposed to 802 and the amount of pulmonary inammation, as measured by neutrophil numerical den- sity (Nn) in each animal was measured after three successive days of air pollution ex- posure. A large value of Nn denotes pulmonary inammation. The data are contained in the le pollution. sas7bdat, and variables CAPS, 802 and Nn are named as caps, $02, and 1m therein. (a) (15 points) Consider the main effect model and the interaction model (which con- tains both main effects and interactions) that simultaneously assess two categorical factors (802 and CAPS). Write down these two regression models, making sure to explicitly dene all independent variables. Write out the interpretation of each regression coefficient Specied in each of these two models. (b) (10 points) Consider a test of whether there is a difference in the health effects of air pollution inhalation for healthy animals and that for chronic bronchitic animals (i.e. those who received 802) under the interaction model. What is the null hypothesis correSponding to this test, in terms of the regression coefcients under the interaction model