Triangle jkl has been reflected over the y-axis. which of the following best describes the relationship between the y-axis and the line connecting k to k′?

they share the same midpoints.
they are diameters of concentric circles.
they are parallel and congruent.
they are perpendicular to each other.

Find the value of the cosine for angle a

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

If it 8 inch candle burns at 7/10 inch per hour and a 6 inch candle burns at 1/5 inch per hour after how many hours would both candles be the same height