Can someone please help me with the question i really don’t get it

Data was collected on myrtle beach for 11 consecutive days. each day the temperature and number of visitors was noted. the scatter plot below represents this data. how many people visited the beach when the temperature was 84 degrees?

You paid 28.00 for 8 gallons of gasoline. how much would you pay for 15 gallons of gasoline?

The function f(x)= x5+ ( x + 3)2 is used to create a table. if x = -1 then what is f(x)?