Answer:
a.
b.
c.
Explanation:
This rectangle is made up of two 30-60-90 right triangles, which have special properties that are worth memorizing for the future. Please see the attached picture.
Using this information, we can deduce that the top and bottom sides are equal to
.
From the properties of a rectangle we know that the right side is 12.
The diagonal is equal to
.
We can find the area by doing
,
And the perimeter is equal to