<span>Cu⁺ is the only one of the ions in the list that will show 8 electrons in a d sublevel....its configuration will be Ar| 4s² 3d⁸
hope this helps</span>
Answer:
When this equation is solved, the two values of the unknown are 0.0643 and -0.082
Explanation:
Given
--- the actual equation
Required
The values of x
We have:

Cross Multiply

Multiply both sides by 100

Open bracket

Rewrite as:

Using quadratic formula:

Where:

So, we have:



Split



The answer is A.
Gravity acting on the edges of plates and convection in the mantle