What system of units do scientists use to measure the properties of matter

Acatapult is tested by roman legionnaires. they tabulate the results in a papyrus and 2000 years later the archaeological team reads (distances translated into modern units): range = 0.4 km; angle of launch = π/5 rad; landing height = launch height. what is the initial velocity of launch of the boulders if air resistance is negligible?

In 1980, alfa romeo introduced the first system to smooth a rough idle caused by ignition and camshaft timing changes.

What is the measurement of how fast an object moves relative to a reference point?