Agirl is snorkeling 1 meter below sea level and then dives down another 0.5 meters. how far below sea level is the girl

(note i put the graph in so plz )the graph shows the amount of water that remains in a barrel after it begins to leak. the variable x represents the number of days that have passed since the barrel was filled, and y represents the number of gallons of water that remain in the barrel. what is the slope of the line

How do i do this? i don’t understand

On a piece of paper, graph y< x+1. then determine which answer matches the graph you drew.