Answer:
Drone = $300
4 Extra Set Of Propellor = 4(25$) = $100
Step-by-step explanation:
True, all of them represent a negative number, for example:
You have $60 and you spent $10, the remaining money is:

Your savings are $1000 and you make a Withdrawal of $500:

In other words for calculation purposes, they all have negative values
More then 2 thats the only answer I can give
12x40=480
You can first multiply 12x4=48 and then you could put a zero next to the 8