I don’t know the answer

I believe the answer would be yes. Since your dealing with Ratios it would be simple to understand that they are proportional. I'll explain a little better.

This means that if you double this ratio, it will still be equivalent to 1:3

1:3

This is also proportional because this number will always be equivalent to itself.

7:21

Hope this helps

-Miri

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.