Ick! Word problems! They suck. Okay so first of all you want to narrow it dow the equation.
Step 1. What are the numbers? (In this case 12 m/s and 25 m/s)
Step 2. Are you multiplying, dividing? (In this case your dividing)
Step 3. Divide.
I hope that helps.
(1) The position around equilibrium of an object in simple harmonic motion is described by

where
A is the amplitude of the motion

is the angular frequency.
The velocity is the derivative of the position:

where

is the maximum velocity of the object.
The acceleration is the derivative of the velocity:

where

is the maximum acceleration of the object.
We know from the problem both maximum velocity and maximum acceleration:


From the first equation, we get

(1)
and if we substitute this into the second equation, we find the angular fequency

while the amplitude is (using (1)):

(b) We found in the previous step that the angular frequency of the motion is

But the angular frequency is related to the period by

and so, the period is
<span>covalent bond I think </span>
Answer:
Explanation:
electron attraction between electron and nucleus = centripetal force of the orbiting electron
In fact, Bohr model depicts the atom as a nucleus surrounded by electrons in circular orbit around it, similar to the planets around the Sun. The centripetal force that keeps the electrons in circular motion around the nucles is provided by the electrostatic force between the electrons and the nucleus.
There are no such examples on the list you've provided.