The graph above represents a step function. A graph of a step function resembles the steps of a staircase and is not continuous. The black dot represents a closed endpoint (to include) and the white dot represents an open endpoint (do not include). Utilizing the graph, how much does it cost to park for 121 mins? a. $3 c. $9 b. $6 d. $12 Please select the best answer from the choices provided