Which is true about UVA and UVB rays? A. Both rays can be blocked 100% by sunscreen
B. UVA protects the surface, UVB protects beneath the surface
C. UVB rays cause burning, UVA rays cause premature aging
D. UVA rays cause burning, UVB rays cause premature aging

I need help :

The a992 steel rod bc has a diameter of 50 mm and is used as a strut to support the beam. determine the maximum intensity w of the uniform distributed load that can be applied to the beam without risk of causing the strut to buckle. take f.s. = 2 against bucklin

The two required components for a generator are

Asmall object with mass 0.200 kg swings back and forth on the lower end of a light rope that is 3.00 m long. the upper end of the rope is attached to the ceiling. as the object swings through its lowest position, where the rope is vertical, the speed of the object is 5.80 m/s. at this point in the motion, what is the tension in the rope? (use g = 9.80 m/s2.)