Hannah drew a pattern using only equilateral triangles. which of the following statements about an angles in an equilateral triangle is true?
a. the measure of each angle is 60 degrees
b. the measure of each angle is 120 degrees
c. the measure of one of the angles is 90 degrees
d. the measure of one of the angles is more than 180 degrees

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters