John swims 22 feet below sea level and then swims 12 feet up to his friend. The total number of feet John swims can be represented by what expression?

Write the system of equations represented by the matrix. 0 1 2 4 -2 3 6 9 1 0 1 3

Plz help plz give me the answer

Starting at home, emily traveled uphill to the hardware store for 606060 minutes at just 666 mph. she then traveled back home along the same path downhill at a speed of 121212 mph. what is her average speed for the entire trip from home to the hardware store and back?