Positively-charged molecules CAN diffuse straight through the plasma membrane.

the cost of mining is extremely low compared to the money earned from mining, creating income to improve the environment.

in a chemical reaction, the atoms and molecules produced by the reaction are called products. no new atoms are created, and no atoms are destroyed. in a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.