Can anyone help me ???

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?

Acable company claims that the average household pays $78 a month for a basic cable plan, but it could differ by as much as $20. write an absolute value inequality to determine the range of basic cable plan costs with this cable company. a. |x − 78| ≥ 20 b. |x − 20| ≥ 78 c. |x − 20| ≤ 78 d. |x − 78| ≤ 20

What is the value of x in the equation 1/5x - 2/3y = 30 , when y = 15