Corey stepped back 59.71 feet to get a better view of the bird.
Explanation:
This is a right angled triangle. Let
be the angle of elevation.
Let the adjacent side of the triangle be x for the angle 
Let the opposite side of the triangle by y for the angle 
Thus,

Since, the height of the tree is 80 feet, 
To find the value of x, let us substitute
and 

Since, Corey moves back a few steps to gain a better view of the bird, the angle of elevation is 41°
Now, we shall find the x for
and 

To find how many feet Corey step back is to subtract the value of two adjacent sides, thus,

Thus, Corey stepped back 59.71 feet to get a better view of the bird.
Yes it is yes yes yes yes it is
Answer:
21
Step-by-step explanation:
Good luck ..have a nice day
D is the only viable answer among these, as A, B, and C all contain two even integers which, by definition, have a greatest common factor of 2.
<em>Correction: </em>I was incorrect in saying that <em>all </em>even integers have a greatest common factor of 2; 2 is at least guaranteed to be <em>one of the common factors </em>in any group of even numbers, but these examples all have it as their <em>greatest </em>common factor as well.
The answer is 21% I hope this helps