Question 927274
solution posted below
*[illustration solution_927274].
hope this helps!
Also, to state your final answer in part b, substitute k back in to get a final equation of
y={{{(3/2000)*(x)^2+40}}}
{{{ graph( 500,500, -200, 200, 0, 100, (3/2000)*(x^2)+40) }}}