Don't get this at all, could someone explain it?

What set does not contain -3 the set of all real numbers the set of all integers the set of all whole numbers the set of all rational numbers

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76

Will mark the brainliest.paula makes stained-glass windows and sells them to boutique stores. if her costs total $12,000 per year plus $4 per window for the frame. how many windows must she produce to earn a profit of at least $48,000 in one year if she sells the windows for $28 each?