Answer:
We need to remember that we have independent events when a given event is not affected by previous events, and we can verify if two events are independnet with the following equation:

For this case we have that:

And we see that 
So then we can conclude that the two events given are not independent and have a relationship or dependence.
Step-by-step explanation:
For this case we can define the following events:
A= In a certain computer a memory failure
B= In a certain computer a hard disk failure
We have the probability for the two events given on this case:

We also know the probability that the memory and the hard drive fail simultaneously given by:

And we want to check if the two events are independent.
We need to remember that we have independent events when a given event is not affected by previous events, and we can verify if two events are independnet with the following equation:

For this case we have that:

And we see that 
So then we can conclude that the two events given are not independent and have a relationship or dependence.
I can help if you put the number sentences in
Answer:
16. r(s)(t) =
r=2, s=3, t=4
(2)(3)(4)=
(2*3) = 6 ---> 6(4) = 24
final: 24
17. (r)(s)(t)(x)(y) =
r = 2, s = 3, t = 4, x = 5, y = 6
(2)(3)(4)(5)(6)
2*3=6
6*4=24
24*5= 120
120*6=720
final: 720
18. (7x + 2Y) =
x = 5, y = 6
rewrite---> = [7(5) + 2(6)]
[35 + 12] = 47
final: 47
hope this helpsss sorry took a while LOL
Step-by-step explanation:
q = 1; r = 2; s = 3; t = 4; x = 5; y = 6