Which of the following numbers is a composite number?
OA) 13
OB) 31
OC) 49
OD) 67

Step-by-step explanation:

First you will need to know what a composite number is.

A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Equivalently, it is a positive integer that has at least one divisor other than 1 and itself.

see pic below

I think it would be OC) 49

(Because that is a composite number.)

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