Question to the care of the figure below

Sara sells beaded necklaces she makes a profit of 4 dollars pn every neclace she sells which table represents the profit sara makes

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Empty box + box + empty box fill in the box is equal to 30 how