A cold front forms when A.
cold air rises and creates a vacuum.

B.
cold air moves under warm air and pushes the warm air upwards.

C.
warm air collides with cold air, but neither has enough energy to move above or below the other.

D.
warm air moves in below existing cold air and pushes the cold air upwards.

What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons? a) 6 b) 8 c) + 1 d) 12 e) 18

Acm ruler with main graduations from 1 to 10 from left to right there are 10 secondary graduations between each of the main graduations there is a line that begins. at the left end of the ruler 10 secondary graduations to the left of the “1 main graduation the right end of the line ends on the eighth secondary graduation to the right of 3 how long is the line

What type of chemical bond is formed between two atoms of bromine 1. metallic 2. hydrogen 3. ionic 4. covalent