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 ageing.
​d. UVA rays cause burning, UVB rays cause premature ageing

C

Whoever thinks A, you are an idiot. No sunscreen can block 100% of sun, unless coated on to the point of your entire body being the color of industrial white.

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.