Let the four consecutive numbers be x, x+1, x+2, and x+3.
The sum of the four numbers is 54, therefore
x + (x+1) + (x+2) + (x+3) = 54
4x + 6 = 54
4x = 54 - 6 = 48
x = 12
Answer:
The four numbers are 12, 13, 14, and 15
Check the picture below.
notice, we have three pair of sides, let's add them all up to get the area

The trick with answering your 10s, 100s, 1000s, etc, is just adding zeroes onto the ends of the first number. So, since this is 14 times 1000, you would add 3 zeroes onto 14. So your answer is 14,000. Hope this helped!
It depends how you name the sides of triangle.
Look at picture at the result.

PS. Sorry for my terrible drawing but I did it as fast as possible :)