What is surface tension??

Which of the following list the divisions of the geologic time scale in order from longest to shortest

Ahole in the ground in the shape of an inverted cone is 14 meters deep and has radius at the top of 11 meters. the cone is filled to the top with sawdust. the density of the sawdust depends upon the depth, x, following the formula ρ ( x ) = 2.5 + 1.2 e − 0.7 x kg/m3. find the total mass of sawdust in the conical hole.

The energy of a photon is equal to (what) times (what) of the photon.