What is the area of the rectangle part of the following composite figure

The area of the rectangle shown is (4 ft)(12 ft) = 48 ft^2.

i believe the correct answer is b.

in geometry, parallel lines are lines in a plane which do not meet; that is, two lines in a plane that do not intersect or touch each other at any point are said to be parallel. by extension, a line and a plane, or two planes, in three-dimensional euclidean space that do not share a point are said to be parallel.