Given the points plotted on the Coordinate Plane:
• You can find the length of the segment BC by finding the distance between the points B and C.
You need to use the formula for calculating the distance between two points:

Where the following are the two points:

In this case, you can identify that:

Then, by substituting the corresponding coordinates into the formula and evaluating, you get:

• You can find the length of the segment FG by finding the distance between the points F and G.
Notice that:

Using the same formula, you get:

• Notice that:

Using the same formula, you can find the length of the segment AC:

• You can identify that:

Then, the length of the segment DE is:

• Notice that:

Then, the length of the segment AB is:

• You can find the length of the segment EF:

Hence, the answer is: