<h2>
Hello!</h2>
The answer is:

<h2>
Why?</h2>
To solve the problem we need to add/subtract like terms. We need to remember that like terms are the terms that share the same variable and the same exponent.
For example, we have:

We have that we were able to add just the terms that were sharing the same variable and exponenr (x for this case).
So, we are given the expression:

Hence, the answer is:

Have a nice day!
The answer is 95%
This is something you should memorize. Specifically it is from the Empirical Rule (or 68-95-99.7 rule) which gives rough approximations of areas under the curve.
Answer:
Please refer to the attachment
Since simple interest doesn't involve compounding, the same amount gets added on every year. So, the equation for the simple interest received is

, where

is the total interest,

is the original deposit (or "principal"),

is the interest rate, and

is the time passed in years.
Plugging in our values, we can solve for the interest rate:


