Answer:
0.2081 = 20.81% probability that at least one particle arrives in a particular one second period.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
e = 2.71828 is the Euler number
is the mean in the given interval.
Over a long period of time, an average of 14 particles per minute occurs. Assume the arrival of particles at the counter follows a Poisson distribution. Find the probability that at least one particle arrives in a particular one second period.
Each minute has 60 seconds, so 
Either no particle arrives, or at least one does. The sum of the probabilities of these events is decimal 1. So

We want
. So
In which


0.2081 = 20.81% probability that at least one particle arrives in a particular one second period.
Yes they should reach the 8.1 mile marker by noon
2 hours equals 6 miles 2.4+6=8.4
if they kept walking for a full 2 hours they would reach the 8.4 mile marker
C because i learned it from xxxx xxx
7 is 1/4 of 28, so 7 is 25% of 28.
The drop from 28 to 7 is a drop of 21.
21 is 3 times 7, so 21 is 3 times 25%.
Answer: It is a 75% decrease.