The sun generates both mechanical and electromagnetic waves. Which statement about those waves is true?

Abeam has a square cross-section, a x a, where a is the linear dimension, and is subject to a pure bending moment, m. m is known with an uncertainty of 10% and a is known with an uncertainty of 5%. the strength of the material is known to an uncertainty of 12%. find the minimum design factor such that the beam is guaranteed not to fail.

Animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. reactivate d) a dog is getting hot in the sunlight, so he moves to a shaded area.

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?