I would say d. Hope that helps
21 hrs. Because if Harry worked one third the hrs thats Aiden worked then 7×3 =21 and 21÷3=7. So 7 is one third of 21.
Bill paints 1/2 per hour. Bob paints 1/3 per hour. 1/2x+1/3x=1
The vertex is ( 2,4)
The axis of symmetry is 2 .
Direction of parabola ( i don’t know sorry )