I'll start 18 and 22 for you, and you should then be able to do the rest on your own!
For 18, what we literally do is apply the distance formula for all the points and add them up. For B to C, we get the distance between them to be
sqrt((x1-x2)^2+(y1-y2)^2)=sqrt((0-4)^2+(3-(-1))^2)=sqrt((-4)^2+4^2)=sqrt(16+16)=sqrt(32). Repeat the process for C to E, E and F, and F to B then add the results up to get your answer!
For 22, since the area of a rectangle is length*width (we know given the right angles and that the opposite sides are equal in how long they are), we can multiply 2 perpendicular lines, for example, BC and CE to get sqrt(32)*sqrt(8)=16 as the area
What is the rest of the expression?
Answer:
Standard form of

Step-by-step explanation:
Here, the given expression is 
Now, simplifying the above expression in parts, we get

hence, combining both parts:


= 
The above expression is of the STANDARD FORM: 
Hence, the standard form of

To check if a relation is a function, given a mapping diagram of the relation, use the following criterion: If each input has only one line connected to it, then the outputs are a function of the inputs.
Answer:
The diagonals are not congruent should be the answer...
Step-by-step explanation:
Might wanna get another opinion but im pretty sure im right.