Need the last two questions i really don’t understand this

For number 9, you would use the distance formula. 
w: (-6,4)
x: (6,8)

Distance formula: 

x2=6
x1=-6
y2=8
y1=4



= 16.97

10 is pretty easy. Billion= 1,000,000,000. To convert 568,000,000,000 to scientific notation, you first need to make 568 to a number that is greater than 1 but less than 10. So, 568 becomes 5.68. Now, you need to make up for the decimal points. Billion has 9 zeros, so just add 2 more. 5.68 x 10^11.

8doors on the second floor

Need the graph to answer this.