Answer:

Step-by-step explanation:
we know that
<u><em>Combinations</em></u> are a way to calculate the total outcomes of an event where order of the outcomes does not matter.
To calculate combinations, we will use the formula

where
n represents the total number of items
r represents the number of items being chosen at a time.
In this problem

substitute

simplify



The price before tax is $15.52
Answer:
Plane T
Step-by-step explanation:
The given points A, D, and E are shown as being on the plane T as follows
Point a lays on the boundary of the boundary between plane S and plane T
Points D and E are points on a line DE that is on the plane T
Therefore, given that the line DE and the point A all lay on the same plane T, the plane that contains points A, D, and E, is plane T.
Please find the attachment for a better understanding of the explanation to this question.
As we can see from the diagram attached, the X axis represented by XX' and the Y axis represented by YY' intersect each other at the origin represented by O. Further, we notice that this intersection is at the angle 90 degrees or in other words the intersection is perpendicular. Thus, we have seen that the the x and y axes in the xy plane intersect perpendicularly. And hence, the answer is TRUE.
Please note that this is always the case and this is also known as orthogonality.