Answer:
can u help answer mine
Step-by-step explanation:
Answer : 0.0129
Step-by-step explanation:
Given : Based on FAA estimates the average age of the fleets of the 10 largest U.S. commercial passenger carriers is
years and standard deviation is
years.
Sample size : 
Let X be the random variable that represents the age of fleets.
We assume that the ages of the fleets of the 10 largest U.S. commercial passenger carriers are normally distributed.
For z-score,

For x=14

By using the standard normal distribution table , the probability that the average age of these 40 airplanes is at least 14 years old will be :-

Hence, the required probability = 0.0129
Answer:
the second one
Step-by-step explanation:
Step-by-step explanation:
We know that tan=sin/cos, so tan(x+π/2)=

Then, we know that sin(u+v)=sin(u)cos(v)+cos(u)sin(v),
so our equation is then
Then, cos(u+v)=cos(u)cos(v)-sin(u)sin(v), so our expression is then
