Negative, because Correlation and slope have the same direction (Sxy will be negative)
We know that
The formula for combinations is
C=n!/[(n-r)!*r!]
where
n is the total number of objects you choose from
r is the number that you choose to arrange
in this problem
n=15 students
r=4 students
C=15!/[(15-4)!*4!]-----> C=15!/[11!*4!]---> (15*14*13*12*11!)/(11!*4*3*2*1)
C=(15*14*13*12)/(24)----->C=1365
the answer is
1365
Answer
Find out the what is the value of x when y = 8 .
To prove
As given
The variables y and x have a proportional relationship.

y = kx
Where k is the constant of proportionality.
As y = 5 when x = 4
Put in the above
5 = 4k

Now find out the value of x , when y = 8


x= 6.5
Therefore when y = 8 than x = 6.4
5,7 and 8 are right angles, and 6 is an acute angle this is because of u look at 9 and 10 you can see a little box looking thing under the h and if u do that to all of them 5, 7 and 8 can fit the little box but 6 you can’t because it is an acute angle. Hope this helped!