An open circle on the number line means that the number a possible solution.

well it isn't in the solution it would be an inequality that doesn't have a line under it

if it has a line under the inequality then it would be included in the solution

Step-by-step explanation:

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m