Expand 3(x+4) I don't understand

3382-299=3383- ? fill in the blank?

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?

On average a herd of elephants travels 10 miles in 12 hours you can use that information to answer different questions drag each expression to show which is answers