Parabolic expression/vertex/velocity etc.. HELP

I have been trying to figure out this problem since two days ago... I'm stuck.. and need help. I'm missing something, I suspect maybe with the fact that a parabolic expression is ax^2 + bx + c and the one below is not set up that way... Not looking for the answers, just some steps on each question.. then hopefully it will turn the light on in my head.. Thank you

Something fired at a 45 degree angle has an initial velocity of 340 ft/sec in both vertical and horizontal directions.. the equation is then

h(t) = -16t^2 + 340t

1. What is the ordered pair which constitutes the vertex of our parabolic expression h(t)

2. How high will our projectile ascend? How long does the projectile take to gain that maximum height?

3. What are the ordered pairs corresponding to the zeros of our parabolic expression h(t) (solutions to the equation -16t^2 + 340t=0)

4. How long does it take for our projectile to reach it's destination.