This is no mistake he is the one
Number 4 is arithmetic explicit
Number 1 is arithmetic recursive
Number 2 is geometric explicit
Number 3 isgeometric recursive
1, 3/3, 420/420 why such a wierd qustion
Since a and 5 aren't like terms, you would write the expression as 
Answer:
2257m3
Step-by-step explanation:
50x25x2=2500
2500-243=2257