6. 4+ 22x lim T--00 5 - 3e3x = (a) (b) $ (c) ; (d) (e) none of the above is true 7. If lim r' T-700 AT = 0 for any real number r, then er + 2100 lim e2: + x2 = T-+00 (a) -2 (b) -1 (c) o (d) 1 (e) none of the above is true 8. lim x 1+ 1 = T-+00 (b ) (c) = (d) (e) none of the above is true