If
and
are perpendicular, then their dot product is zero. This means

Solving for n is trivial; it follows that n = 3.
Newton's second law states that the force applied to an object is equal to the product between the mass m of the object and its acceleration a:

Using

and

, we can find the value of the force applied to the roller-blade to obtain this acceleration:
Explanation:
So what's the question here?
Maybe cuz your fat fat biches
Answer:
Half-life units in 'years' & 'seconds' are the most widely used, but actually, whatever you wish ... sec, min, hrs, days, yrs. The application and one's preference could dictate more appropriate units.
Explanation: