The height of a pop fly ball over the time after the ball is hit is modeled by the function h(t) = -16t²+81t+5 where h(t) is the ball's height in feet above the ground and t is the time in seconds after the ball is hit. In how many seconds will the ball reach its maximum height?

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Acompany manufactures large valves, packed in boxes. a shipment consists of 1500 valves packed in 75 boxes. each box has the outer dimensions 1.2 x 0.8 x 1.6 m and the inner dimensions 1.19 x 0.79 x 1.59 m. the boxes are loaded on a vehicle (truck + trailer). the available capacity in the vehicle combination is 140 m3. each valve has a volume of 0.06 m3. - calculate the load factor on the box level (%). - calculate the load factor on the vehicle level (%). - calculate the overall load factor (%).

Wich statement could be used to explain why the function h(x)= x^3 has an inverse relation that is also a function