Answer:
a)
And we can find this probability with the complement rule:
b) 
And if we use the z score we got:
Step-by-step explanation:
Let X the random variable that represent the lengths of a population, and for this case we know the distribution for X is given by:
Where
and
Part a
We are interested on this probability
And we can use the z score formula given by:
And using this formula we got:
And we can find this probability with the complement rule:
Part b
For this case we select a sample of n =44 and the new z score formula is given by:

And if we find the z score we got:

And if we use the z score we got:
X is equal to 28 and Y is equal to 23
Answer:
The tree is 28 feet tall.
Step-by-step explanation:
It is given that:
Height of flag pole = 8 feet
Shadow of flag pole = 6 feet
Ratio of height to shadow = 8 : 6
Shadow of nearby tree = 21 feet
Height of nearby tree = x
Ratio of height to shadow = x : 21
8 : 6 :: x : 21
Product of means = Product of extremes
6x = 8*21
6x = 168
Dividing both sides by 6

Therefore,
The tree is 28 feet tall.
Answer:
3 x^3 y^4 sqrt(5x)
Step-by-step explanation:
sqrt(45x^7y^8)
We know that sqrt(ab) = sqrt(a)sqrt(b)
sqrt(45)sqrt(x^7) sqrt(y^8)
sqrt(9*5) sqrt(x^2 *x^2 * x^2* x) sqrt(y^2 *y^2 *y^2 *y^2)
We know that sqrt(ab) = sqrt(a)sqrt(b)
sqrt(9)sqrt(5) sqrt(x^2)sqrt(x^2) sqrt(x^2) sqrt(x) sqrt(y^2)sqrt(y^2)sqrt(y^2)sqrt(y^2)
3 sqrt(5) x*x*x sqrt(x) y*y*y*y
3 x^3 y^4 sqrt(5)sqrt(x)
3 x^3 y^4 sqrt(5x)