Answer:
a)Both X and Y can be well approximated by normal random variables.
Step-by-step explanation:
For each individual, there are only two possible outcomes. Either they are right-handed, or they are left-handed. This means that we can solve this problem using concepts of the binomial probability distribution.
Binomial probability:
Probability of exactly x sucesses on n repeated trials, with probability p.
The binomial probability can be well approximated by normal random variables, using the expected value
and the standard deviation 
Let X be the number of males (out of the 100) who are left-handed.
and
. Can be well approximated.
Let Y be the number of females (out of the 80) who are left-handed.
and
. Can be well approximated.
The correct answer is
a)Both X and Y can be well approximated by normal random variables.
Answer:
16,002
Step-by-step explanation:
Volume generated by the areas R2 + R3 around the line OC
= (1/3) pi 1^2 * 3 = pi sq units
Volume generated by area R2 around OC is found as follows
the equation of the curve can be written as x = y^4 / 81
Integral between limits y = 0 and 3 of the curve is
pi INT x^2 dy = INT pi y^8 / 81^2 dx
= pi [3^9 / 9*81^2]
= pi/3
So the volume generated by R3 about OC = pi - pi/3 = 2pi/3