Question on picture please help

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value

Which of the following bonds would be most polar? a. c-i b. c-br c. c-cl d. c-f e. c-o

Which are causes of mechanical weathering? (check all that apply) a. acid rain b. plant growth c. animal actions d. carbon dioxide e. pressure release i chose b & e and got the question wrong.