Please answer the last conversion !! 531 ms to s

Inez has a phone card. the graph shows the number of minutes that remain on her phone card a certain number of days.

Over the last 8 nights, elyse earned the following in tips: {105, 120, 84, 95, 100, 132, 140}. if she earns $140 a night for the next four nights, which measure of center would increase more, the mean or median?

X2 + y 2 = 36 x + y = 6 solve the system of equations.