What type of fossil forms when the impression from the remains of an organism is filled in with soil and hardens into the shape of the original organism?

In a reaction (at equilibrium) that makes more moles of gas than it consumes, what is the effect of increasing the pressure?

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

What are the first two quantum numbers for the electrons located in subshell 4d? what are the first three quantum numbers for the electrons located in subshell 2s? how many electrons can be held in a sublevel l = 3? how many electrons can be held in the energy level n = 4? how many electrons in an atom can share the quantum numbers n = 4 and l = 3?