2. (Six parts; 22 marks in total) Persistent patent ductus arteriosus (PDA) is a medical condition that affects many very low-birth weight infants. Infants with PDA have an increased risk of serious ailment such as severe heart failure. The Apgar score is used to assess the health of an infant one minute after birth. The oneminute Apgar score measures how well the newborn tolerated the birthing process. A score of seven to 10 is normal and indicates the newborn is in good condition. Any score less than seven indicates that the baby needs assistance such as helping the infant breathe. Airway pressure is a measure of respiratory status, usually measured seven days after birth. Some researchers determined that early ibuprofen administration might prevent PDA in preterm neonates. A sample of 130 such infants was randomly divided into 4 groups. 32 were treated with one dose of ibuprofen, 33 with two doses, 33 with three doses, and 32 with a saline solution. The following is the description of variables under study. Variable Description of Variables Gender Male 0R Female, Dose Dose of ibuprofen (an integer from 0 to 3), Weight Birth weight (in pounds), Age Gestational age (in weeks), Score One-minute Apgar score, Pressure Airway pressure (in cm H 20) seven days after birth. Define variables Gender and Dose using the following indicator variables: male = 1 for a Male and male = 0 for a Female, 01 = 1 if Dose of ibuprofen is 1 and D1 = 0 otherwise, DZ = 1 if Dose of ibuprofen is 2 and D2 = 0 otherwise, D3 = 1 if Dose of ibuprofen is 3 and D3 = 0 othenivise. Note: No output is needed for questions (a) to (c). Consider the following regression model with pressure as the response: y{pressure| weight, GENDER, DOSE} = ,6}, + lweight + zmale + AD] + 4D2 + 5D3 + ,66 (weight x male) + ,6, (weight >