Answer:
The t distribution is used, because we have the standard deviation for the sample.
Step-by-step explanation:
When to use the z or the t distribution?
When we have the standard deviation for the population, we use the z distribution.
When we have the standard deviation for the sample, we use the t distribution.
In this question:
We have the standard deviation for the sample, which means that the t distribution is used.
<h3>The given expression as single exponent is:</h3>

<em><u>Solution:</u></em>
<em><u>Given expression is:</u></em>

In exponents,
When the base is same, exponents can be added
Which means,

Therefore,

Thus the given expression as single exponent is:

The value of the function f(x) = x² + 6x - 9 when x = -5 is -14.
<h3>What is an equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
An independent variable is a variable that does not depends on other variable while a dependent variable is a variable that depends on other variable.
Given that:
f(x) = x² + 6x - 9
When x = -5:
f(-5) = (-5)² + 6(-5) - 9 = -14
The value of the function f(x) = x² + 6x - 9 when x = -5 is -14.
Find out more on equation at: brainly.com/question/2972832
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