Mahoo
That one, there!
You use exactly the same instruments to measure speed in the metric system as you use in any other system. For example, a speedometer, or a distance measuring device and a stopwatch. The difference is that these devices are calibrated in metric units, instead of old-fashioned units.
300 million meters per second
A time graphs units is what is used for the y-axis. This is what show the speed in time.
km/hr is a standard measure of speed in metric units. The speed of a train is usually quoted in km/hr or miles/hr, depending on the whether metric or Imperial/US units are being used, which varies from country to country.
Metric units include millimeters, centimeters, decimeters, and meters.
SI and metric are the same units.
metric units are used for everything in Canada
If the graph is traveling at a constant speed of 1 unit per minute, then after 5 seconds it would have traveled 5/60 = 1/12 units. Therefore, the speed at 5 seconds is 1/12 units per second.
"Metric conversion" refers to the change from English units of measurement to metric units.
9,899 metric units
The information given by the slope of ("on") a distance-time graph is the SPEED. The size ("magnitude") of the slope is the size of the speed and the units of the distance axis are divided by the units on the time axis to give the units of the speed ... so if your distance is in miles and time is in hours then your speed will be in miles per ("divided by") hours (mph)... but if distance is in metres and time is in seconds then the speed is in metre per second (m/s).