7. (T 3 Marks) A(:)=1EIUEI 1.035\" A $1000 investment grows according to the function , where A is the amount of the investment after t years. At what rate is the investment growing after 5 years? 8. (T 4 + C 1 Marks) Find the scalar equation of the plane passing through the points: A (0, 1, 2), B(3 ,3 ,0) and C{5, 1, 0) (Draw a rough sketch (not to scale ) representing the problem 9. (C 4 Marks) Sketch the function f ( x ) = -: 1 x2 ( x2 + 4x -21) 10 indicating any intercepts, extrema, points of inflection, and asymptotes if any