Elroy behaves most authentically when he- (A) tacks the envelope to the door
(B) calculates the narrator's wages
(C) whistles to himself
(D) slaps his hands together

we know that, volume of a rectangular prism is given by :

✿   {length × width × height}

given : the length of rectangular prism = 5.5

given : the width of rectangular prism = 6

given : the height of rectangular prism = 3

⇒ the volume of given rectangular prism = {5.5 × 6 × 3}

⇒ the volume of given rectangular prism = 99