Can a quadratic function have both an absolute maximum and absolute minimum, explain?

Plz don't copy, solve correctly will definitely upvote

A farmer is fencing a rectangular area for cattle and uses a straight portion of a river as one side of the rectangle, as illustrated in the figure. Note that there is no fence along the river. If the farmer has 1600 feet of fence, find the dimensions for the rectangular area that gives the maximum area for the cattle. River

A penny is thrown from the top of a 48.9-meter building and hits the ground 3.04 seconds after it was thrown. The penny reached its maximum height above the ground 0.79 seconds after it was thrown. Define a quadratic function, h, that expresses the height of the penny above the ground (measured in meters) as a function of the number of seconds elapsed since the penny was thrown, t.     What is the maximum height of the penny above the ground?