Which telescope is this?

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?

6–43 a food department is kept at 2128c by a refrigerator in an environment at 308c. the total heat gain to the food department is estimated to be 3300 kj/h and the heat rejection in the condenser is 4800 kj/h. determine the power input to the compressor, in kw and the cop of the refrigerator.

The safe load, l, of a wooden beam of width w, height h, and length l, supported at both ends, varies directly as the product of the width and the square of the height, and inversely as the length. a wooden beam 4 inches wide, 9 inches high, and 240 inches long can hold a load of 6810 pounds. what load would a beam 3 inches wide, 8 inches high, and 144 inches long, of the same material, support? (round off your answer to the nearest integer.)