Help me please :(

Determine whether the quadrilateral below is a parallelogram. justify/explain your answer (this means back it up! give specific information that supports your decision. writing just "yes" or "no" will result in no credit.)

Landon wrote that 3−2.6=4. which statement about his answer is true?

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)