I think it is E not very sure but try it
Answer:
(8,9)
Step-by-step explanation:
Given



Required
Determine the 4th point
The coordinate point of a horizontal or a vertical rectangle is given as:
(x1,y1), (x2,y2), (x3,y3), (x4,y4)
Where:

So, we have:
--- 
---- 
---- 
Using the above equations:


Hence, the coordinate of the 4th point is:

Answer:
8)5.1*10⁶
9)6.98*10 to the power of -6
10) 3.000052*10⁰
11)0.006548