Ralph is 3 times as old as sara. in 6 years, ralph will be only twice as old as sara will be then. find ralph's age now.. if x represents sarah's age now, which of the following expressions represents ralph's age in six years? . . a.2x. b.6x. c.2x + 6. d.3x + 6

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