What is 5x + 8y =16 in slope intercept form

What kind of bond pays interest which is exempt from tax?

Which one ? is the answer and how to find this answer

When george started his current job, his employer told him that at the end of the first year, he would receive two vacation days. after each year worked, his number of vacation days will double up to five work weeks (25days) of payed vacation. how many vacation days will he have in 4 years