Question $2$: For each of the sequences described below, indicate which of the following properties describes the sequence, keeping in mind that the sequence may have more than one of the properties, or none of the properties: $(20$ Points$).$

Increasing

Decreasing

Non$-$increasing

Non$-$decreasing

a$)a_n=n^2-5n,$ for $n1(7$ points$)$

b$)a_n=n^2-4n,$ for $n1(7$ points$)$

c$)$ Give numerical values for the following summations. $(6$ points$)$

a$.{\displaystyle \underset{?}{\overset{?}{}}}4k=1(K+2{)}^2$

b$.{\displaystyle \underset{?}{\overset{?}{}}}4j=1(3j-2)$