Answer:
-14a^2b-42ab^2+56abc
Step-by-step explanation:
You can use the FOIL method
multiply the first numbers
then inner
then outer
then last
Answer:
The total nuber of hours that the battery can be used over its lifetime is 600.
Step-by-step explanation:
We use an infinite geometric series to solve this question.
The sum of all values of an infinite geometric series is given by the following equation:

In which
is the first term and r is the common ratio.
After each charging, a battery is able to hold only 97% of the charge from the previous charging.
This means that 
The battery was used for 18 hours on its first charge before it had to be recharged.
This means that 
What is the total number of hours the battery can be used over its lifetime?

The total nuber of hours that the battery can be used over its lifetime is 600.
Answer:
b. 0.25
c. 0.05
d. 0.05
e. 0.25
Step-by-step explanation:
if the waiting time x follows a uniformly distribution from zero to 20, the probability that a passenger waits exactly x minutes P(x) can be calculated as:

Where a and b are the limits of the distribution and x is a value between a and b. Additionally the probability that a passenger waits x minutes or less P(X<x) is equal to:

Then, the probability that a randomly selected passenger will wait:
b. Between 5 and 10 minutes.

c. Exactly 7.5922 minutes

d. Exactly 5 minutes

e. Between 15 and 25 minutes, taking into account that 25 is bigger than 20, the probability that a passenger will wait between 15 and 25 minutes is equal to the probability that a passenger will wait between 15 and 20 minutes. So:

Answer: C) Plane: 235 km/h, Wind: 24 km/h
Step-by-step explanation:
Given that :
Average Speed while flying with a tailwind = 259km/hr
Return trip = 211km/hr
Let the speed of airplane = a, and wind speed = w
Therefore ;
Average Speed while flying with a tailwind = 259km/hr
a + w = 259 - - - (1)
Return trip = 211km/hr
a - w = 211 - - - (2)
From (2)
a = 211 + w
Substitute the value of a into (1)
a + w = 259
211 + w + w = 259
211 + 2w = 259
2w = 259 - 211
2w = 48
w = 48/2
w = 24km = windspeed
Substituting w = 24 into (2)
a - 24 = 211
a = 211 + 24
a = 235km = speed of airplane