Answer: Our required probability is 
Step-by-step explanation:
Since we have given that
Number of coins = 3
Number of coin has 2 heads = 1
Number of fair coins = 2
Probability of getting one of the coin among 3 = 
So, Probability of getting head from fair coin = 
Probability of getting head from baised coin = 1
Using "Bayes theorem" we will find the probability that it is the two headed coin is given by

Hence, our required probability is 
No, the answer is not 
Since the problem is not telling us the height of Silvio, we are going to assume it is not relevant for our calculations.
Let

the altitude of the incoming plane. We know for our problem that the distance between Silvio and the tower is 3 miles, Also we know that the angle of elevation to the plane is 40°. With this information we can create a triangle as shown in the figure. We need a function that relates the angle of elevation with its opposite and adjacent sides, that function is tangent.




We can conclude that we should use the trig function tangent to model this situation; also, we can conclude that the equation that describes this situation is

.
Answer: D
Step-by-step explanation: Im vv sure, is this a test?