In the figure below, arc SBT is one quarter of a circle with center R and radius 6. If the length plus the width of rectangle ABCR is 8, then the perimeter of the darkened region is

a)

b)

c)

d)

e)

Can you please show the steps? Thanks in advance

hey i forgot a major info. The graph stated that SR is 6, sorry i didn't include it on the graph!!