Final answer:
To convert from m/s to km/h, multiply by 3.6. The motorist's speed is 64.8 km/h.
Step-by-step explanation:
To convert from meters per second (m/s) to kilometers per hour (km/h), we need to use the conversion factor of 1 m/s = 3.6 km/h. So, to find the motorist's speed in km/h, we can multiply their speed in m/s by 3.6.
Given that the motorist is traveling at 18.0 m/s, we can calculate their speed in km/h as follows:
Speed (km/h) = Speed (m/s) x Conversion Factor = 18.0 m/s x 3.6 km/h = 64.8 km/h
Therefore, the motorist's speed is 64.8 km/h.