So 400,000 DVD sales with a 31% decline means in the 1st year following, there will be a decline of 124,000 DVDs sold. So we need to take 400,000 - 124,000, which equals a starting point for year two is 276,000 DVDs.
So a 31% decline on 276,000 = 85,560. So we need to subtract that from 85,560 from 276,000 which is 190,440. So at the end of the second year, DVD sales were only 190,440. That's also out starting point of the 3rd year.
So 31% of 190,440 equals 59,036.4 for the third year of DVD sales. So we need to subtract 59,036.4 from out third year starting point of 190,440, which equals 131,403.6, but since you can't have parts of DVDs, we'll round the decimal point fraction to a whole number to end up with 131,404 DVDs sold in year three.
So after three years of a 31% yearly decline in DVD sales you end up with DVD sales are 131,404
The length of pendulum is 2.485 feet
<h3><u><em>
Solution:</em></u></h3>
Given that,
The formula T= 2pi sqrt(L/32) relates the time, T, in seconds for a pendulum with the length, L, in feet, to make one full swing back and forth
<u><em>Therefore, the given formula is:</em></u>

We have to find the length of pendulum that makes one full swing in 1.75 seconds
So the modify the given equation to find "L"

Substitute T = 1.75 seconds and 

Thus length of pendulum is 2.485 feet approximately
Answer:
The horizontal asymptote is y=0