Answer: There are 64 relations from A to B.
Step-by-step explanation:
Number of relation from set A to B = 

Since, A={Φ,{Φ},{Φ,{Φ}}} and B={1,2}
i.e. Number of elements in set A = 3
Number of elements in set B = 2
So, Number of relation from set A to B = 

Hence, there are 64 relations from A to B.
So you maybe know that

. Now let us try to simplify the expression

There is 4.88% decrease in Olivia's score.
Step-by-step explanation:
Given,
Score on first math test = Old value = 82 points
Score on second math test = New value = 78 points
Change = New value - Old value
Change = 78 - 82 = -4
The negative sign indicates the decrease.
Decrease percent = 
Decrease percent = 
Decrease percent = 4.88%
There is 4.88% decrease in Olivia's score.
Keywords: percentage, difference
Learn more about percentage at:
#LearnwithBrainly
I think it is -160 I’m not sure tho