Define symbol and valency?​

Can someone i have no idea of how to do this.

Monomers are the building blocks of larger molecules, called polymers. for example, proteins are composed of chains of amino acids that are linked together. cellulose is a polymer that makes up plant cell walls. cellulose is made from a chain of c6h10o5 molecules. which monomers are most likely used to produce cellulose? why?

What chemical speeds up the process of decomposition in dead organisms are exposed to it? nitrogen oxygen hydrogen chlorine