An index fossil represents a species that lived during A.
a long interval of Earth's history.
B.
Earth's entire history.
C.
a short interval of Earth's history.
D.
several intervals of Earth's history.
which one is it?

Ascientist measures the speed of sound in a monatomic gas to be 449 m/s at 20∘c. what is the molar mass of this gas?

Is a pencil falling to the floor anon contact force, a force, or a contact force

Given the following information: mass of proton = 1.00728 amu mass of neutron = 1.00866 amu mass of electron = 5.486 × 10^-4 amu speed of light = 2.9979 × 10^8 m/s calculate the nuclear binding energy (absolute value) of 3li^6. which has an atomic mass of 6.015126 amu. j/mol.