This one is actually 30 points chem quesitons

The answers to your questions are below:

Explanation:

Question 31 Silicon and sulphur, because they are in the same period (3)

Question 34 the third option, density is not in the table

Question 37 group 1A alkali metals

Question 38 group 1A, oxygen group

Question 39 They are metalloids

the answer is:  

line graphs show patterns in data with variables that change over time; whereas, circle graphs show data as parts out of a whole (such as out of 100%).