Which of these are linear functions?

The graph shown is the graph of which function?

Lydia collected two sets of data one set of data shows an outlier. which set has an outlier, and which number is the outlier?

Water flows at a steady rate from a tap. its takes 40 seconds to fill a 4 litre watering can from the tap. the rate at which water flows from the tap is halved. complete: 4 litres into cm3