4.2 rounded to the nearest whole number

What is the equation of a parabola y(x) that has a vertex at point (− 1/3 , 0.3) and passes through point (− 2/15 , − 1/2 ).

Aprojectile is thrown upward so that its distance above the ground after t seconds is given by the function h(t) = -16t2 + 704t. after how many seconds does the projectile take to reach its maximum height?

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?