Answer:
There were written records by studying aircrafts before historians know about the past.
Step-by-step explanation:
You would multiply 4 and 3, and 2 and 9 separately, then add them, then subtract 40. Remember PEMDAS.
(4*3) + (2*9) - 40
12 + 18 - 40
-10
Hope that helps
Answer: 2?
Now