Answer:
4) The limit does not exist.
General Formulas and Concepts:
<u>Calculus</u>
Limits
- Right-Side Limit:

- Left-Side Limit:

Limit Rule [Variable Direct Substitution]: 
Step-by-step explanation:
*Note:
For a limit to exist, the right-side and left-side limits must be equal to each other.
<u>Step 1: Define</u>
<em>Identify</em>

<u>Step 2: Find Left-Side Limit</u>
- Substitute in function [Left-Side Limit]:

- Evaluate limit [Limit Rule - Variable Direct Substitution]:

<u>Step 2: Find Left-Side Limit</u>
- Substitute in function [Right-Side Limit]:

- Evaluate limit [Limit Rule - Variable Direct Substitution]:

∴ since
, 
Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Limits
Do you need to show work?
You can find a unit rate when given a rate by dividing the the second number in the rate (if you had 3:4, you would divide 4) by the same number. (in the problem I gave you, you would divide 4 by 4 to get 1 then divide 3 by 4.) Then you would have the unit rate. Sorry if that didn't make any sense.
Answer:
Below
Step-by-step explanation:
To prove that the diagonals bisect each other we should prove that they have a common point.
From the graph we notice that this point is E.
ABCD is a paralellogram, so E is the midpoint of both diagonals.
●●●●●●●●●●●●●●●●●●●●●●●●
Let's start with AC.
● A(0,0)
● C(2a+2b,2c)
● E( (2a+2b+0)/2 , (2c+0)/2)
● E ( a+b, c)
●●●●●●●●●●●●●●●●●●●●●●●●
BD:
● B(2b,2c)
● D(2a,0)
● E ( (2a+2b)/2 , 2c/2)
● E ( a+b ,c)
●●●●●●●●●●●●●●●●●●●●●●●●●
So we conclude that the diagonals bisect each others in E.