Steps of solving linear equations

Arandom sample of 150 high school students were asked whether they have a job. the results are shown in the table. have a job do not have a job male 48 35 female 41 26 select a ord or phrase from the drop-down menus to correctly complete the statements describing the association.

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

What is the gcf of 20c^3-5c^4+30c^6