Answer:
Work done in stretching the spring = 7.56 lb-ft.
Step-by-step explanation:
Normal length of the spring = 8 in or
ft
=
ft
If the spring has been stretched to 11 inch then the stretched length of the spring is = 11 in
=
ft
Force applied to stretch the spring = 12 lb
By Hook's law,
F = kx [where k is the spring constant and x = length by which the spring is stretched]
12 = k(
)
k = 18
Work done (W) to stretch the spring by
ft will be
W = 
= 
= ![18[\frac{x^{2}}{2}]^{\frac{11}{12}}_0](https://tex.z-dn.net/?f=18%5B%5Cfrac%7Bx%5E%7B2%7D%7D%7B2%7D%5D%5E%7B%5Cfrac%7B11%7D%7B12%7D%7D_0)
= 9(
)²
= 7.56 lb-ft
So she earns $60 per day working, but only saves $50. To solve this equation you have to multiply $50 to each day she works. If the total has to be exactly $2,000 then you must multiply 50 x 36.4 and that equals $2,000.
Your answer should be 36.4 days.
Another triple integral. We're integrating over the interior of the sphere

Let's do the outer integral over z. z stays within the sphere so it goes from -2 to 2.
For the middle integral we have

x is the inner integral so at this point we conservatively say its zero. That means y goes from
and 
Similarly the inner integral x goes between 
So we rewrite the integral

Let's work on the inner one,

There's no z in the integrand, so we treat it as a constant.

So the middle integral is
I gotta go so I'll stop here, sorry.
Well first you have to solve for the 1st year so 200*.03, .03 represents the 3%. Which would equal 6 dollars so after the 1st year he would have 200+6=206.
Now you do the second year so do 206*.03, which would equal 6.18 so 206+6.18=212.18
Answer= 212.18
They both have money included.