Answer:
Part a) 
Part b) see the explanation
Part c) The domain for h is
and the range is 
Step-by-step explanation:
Let
h ----> the measure of the third side of triangle
P ---> the perimeter of triangle
Part a) write a function that represents the perimeter P of the triangle
we know that
The perimeter of triangle is equal to the sum of its three length sides
so


Part b) Identify the independent and dependent variables
In this problem
The independent variable or input value is the measure of the third side of triangle h
The dependent variable or output value is the perimeter of triangle P
Part c) Describe the domain and range of the function
we know that
The <u><em>Triangle Inequality Theorem</em></u> states that the sum of any 2 sides of a triangle must be greater than the measure of the third side
Find the possible measures of h
Applying the Triangle Inequality Theorem
1)
--->
---> 
2)
--->
therefore
The domain for h is the interval (3,23)

Find the range
For h=3 ----> 
For h=23 ----> 
therefore
The range is the interval (26,46)
