Look at your speedometer for say, a couple of seconds. Depends on whether or not you are moving on average at a constant speed (speedo won't change much) or whether you're in a polluting traffic jam/queue in which case the speedo will go up and down like a yo yo. to determine the speed, you'd probably need to plot the speed on the speedo against the times at which the speedo speeds were read from the speedo.
Catalysts
a catalyst is something added to a reaction that speeds it up (or lowers the activation energy)
increasing the temp would speed up the whole reaction but not lower the activation energy
so B.
Answer:
The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles (lower chambers of the heart). They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.
Explanation:
Answer: 3.33 m/s
Explanation:
Assuming the questions is to convert 12 km/h to meter per second (m/s), let's begin:
In order to make the conversion, we have to know the following:

And:

Keeping this in mind, we can make the conversion:

Then:

C standards are based on observable, reproducible natural phenomena.