Answer:
50 feet
Step-by-step explanation:

Hope this helps!
9:2 is equivalent because it is dividing each side by the same amount. 18 divided by 2 is 9 and 4 divided by 2 is equal to 2, so 9:2 would be equivalent to 18:4.
That is in standard form already.
Scientific form is 8.24 * 10^-9 answer
Need help with what, i cant draw the scale for you lol.