Answer:7043.82
It would be 4200 x 1.09 which is the interest to the power of 6 for the number of years which would then give you 4200 x 1.09^6. This will then give the answer of 7043.82
The correct works are:
.
<h3>Function Notation</h3>
The function is given as:

The interpretation when Steven is asked to calculate Blue(s + h) is that:
Steven is asked to find the output of the function Blue, when the input is s + h
So, we have:

Evaluate the exponent

Expand the bracket

So, the correct work is:

<h3>Simplifying Difference Quotient</h3>
In (a), we have:


The difference quotient is represented as:

So, we have:

Evaluate the like terms

Evaluate the quotient

Hence, the correct work is:

Read more about function notations at:
brainly.com/question/13136492
A and C are the correct answers
Taking the length of the string to be the hypothenuse and the vertical height above the ground to be the 'opposite' side,
the length of the string
= 70/sin(40°)
= 109 feet