Answer:
a
The distribution of X is normal
b

c

Step-by-step explanation:
From the question we are told that
The population mean is 
The standard deviation is 
Generally given from the question that the amount of time spent alone by the population size is normally distributed then then the distribution of X (i.e the amount of time spent by the sample size (the one Mercurian)) will be normally distributed
Generally the probability that the child spend less than one hour in a day is mathematically represented as

Here 
So


From the z-table the value of

So 
Generally the percentage of children that spends over 3.5 hours unsupervised is mathematically represented as



From the z-table the value of

So 
Answer:
Side lengths of 12,8,8
Step-by-step explanation:
In an isosceles triangle the base is different from the other 2 sides which are the same so
28=12+2x (x being the side of the repeat sides)
14=6+x (divide both sides by 2)
8=x (subtract 6 from both sides) so
Side lengths of 12,8,8
Answer:
24 marbles
Step-by-step explanation:
P( purple) = 2/3 = purple/total
2/3 = 16/total
Using cross products
2 * total = 3 *16
2 * total = 48
total = 24
There are 24 marbles
' 16/165 ' <u><em>IS</em></u> a fraction.