Solve y' = 1-12 using separation of variables and select all options below that are valid solutions. Select one or more: pa. f(x, y) = (3+ + + st - 3) 3 Ob. f ( x, y) = (5- 5+3)3 O c. f (x, y) = (5t - 5+3)3 O d. f (x, y ) = (t-41)3 De. f ( x, y) = (5t - $+3 + 1)3 Of. f ( x, y ) = -1 (-31+13 -7) 3