In the above examples, the only one that is not an example of speed is the option:
"6 miles per hour north". A speed doesn't have a direction added to it. If a statement has a direction added to it, it's velocity, not speed. Speed is a scalar quantity. In other words, it is the rate at which the object covers the distance. Speed does not care about direction. It is also not aware of direction. Velocity, on the other hand, is aware of direction and of speed.
Caffeine can pool minerals from your bone and teeth and that what makes it unhealth
White blood cells surround and digest bacteria. White blood cells produce antibodies that destroy pathogens. The middle one, I don't know yet, and the ones at the bottom, I'm still figuring out.
