Good morning.
We have:

Where
j is the unitary vector in the direction of the
y-axis.
We have that

We add the vector
-a to both sides:

Therefore, the magnitude of
b is
47 units.
Potential energy
potential energy is the stored energy an object has, the bike is not moving and it just sitting on the hill, with the stored energy
Answer:
A. Argon
Explanation:
It is a noble gas, a group which is not reactive.
Answer:
The electron cloud is mostly empty space
Force = mass x acceleration
15 = mass x 4
Mass = 15/4
Mass = 3.75 Kg