00:01
So we're looking at the amount of funds in the bank over time.
00:04
And so these funds are from the years 2010 to 2040.
00:15
And we have a function s of t described as follows.
00:20
This is 0 .1375 t squared plus 0 .5185t plus 0 .78t plus 0 .72.
00:34
And let's see, t equals zero corresponds to 2010.
00:47
That's when the funds started to get, were started to be poured in.
00:54
And s of t is measured in trillions.
01:09
And one last thing, this function is from zero to three.
01:19
So t is in decades.
01:23
So that's going to be an important note for some of our calculations, and it may drastically change our calculations if we don't account for that.
01:36
So let's start with the first part, so part a.
01:42
So how much money was there in 2010 within the accounts? and so for that, remember that t equals zero corresponds to 2010 when the money was first deposited.
02:00
So we just need to find s of zero.
02:05
And that will be our, this number right there, the y intercept.
02:15
So that's 0 .72.
02:18
So the amount here, 0 .72 trillion is the same thing as 720 billion...