What is the molar mass of Ammonium Carbonate?

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

If an area has high air pressure and low humidity, what type of weather will it most likely have? plz !

Which of the following contributes to the structural rigidity of cellulose? adjacent glucose polymers are stabilized by hydrogen bonding. glucose residues are joined by (α1→4) linkages. cellulose is a highly branched molecule. the conformation of the glucose polymer is a coiled structure.