Which graph is not a function? please help asap

Strawberries cause two hours per pound kate buys 5 pounds he gets 20% off discount on the total cost how much does kate pay for the strawberries

How do i do this activity, is appreciated

Suppose that in 2008 , 840,800 citizens died of a certain disease assuming the population of teh country is 399 miliion, what is the mortality rate in units of deaths per 100,000 people?