it is oxygen no doubt about it
I think 55% of 480 is 264
With the properties of rectangle in mind we must perform two verification. Verify to see if opposite sides are parallel and adjacent sides are perpendicular.
We need to determine the slope of each side, using the formula,

<u>Slope of AB</u>




<u>Slope of BC</u>



<u>Slope of CD</u>




<u>Slope of AD</u>



<u>Verify Parallel sides</u>
If the quadrilateral is a rectangle, then opposite sides should have the same slope. But


<u>Verify Perpendicularity</u>
And also the product of slopes of all sides with a common vertex should be -1. But




Since the quadrilateral fails to satisfy all these conditions, the quadrilateral is not a rectangle