On graph paper, graph $\overline{AB}$ if $A(1,6)$ and $B(5,2)$.  

1. Find $AB$ (the length of $\overline{AB}$). Leave your answer in exact form. That is, do not approximate with a decimal. Explain your method.

2. Reflect $\overline{AB}$ across the $y$-axis to create $\overline{A'B'}$. What type of shape is $ABB'A'$ if the points are connected in order? Then find the area of $ABB'A'$.

   Hint (b):

   Isosceles trapezoid, the area formula is $\frac{\left(\text{base }1+\text{base }2\right)\left(\text{height}\right)}{2}$.