A study is conducted in patients with HIV. The primary outcome is CD4 cell count which is a measure of the stage of disease. Lower CD4 counts are associated with more advanced disease. The invesitgaors are intereated I nteh association between vitamin and mineral supplements and CD4 count. A multiple regression analysis is performed relating to CD4 count to use of supplements (coded as 1=yes, 0=no) and to duration of HIV, in years (I.E the number of years between the diagnosis of HIV and the study date) For the analysis Y=CD4 count

Y = 302 + 15.1 Supplements- 18.6 Duration of HIV

1) A)What is the expected CD4 count for patient taking supplements who has had HIV for 2.5 years?

Y=

b) What is the expected CD4 count for a patient not taking supplements who was Diagnosed with HIV at study enrollment?

Y=

c) What is the expected CD4 count for a patient not taking supplements who has had HIV for 2.5 years?

Y=