Answer:
Step-by-step explanation:
This is a differential equation problem most easily solved with an exponential decay equation of the form
. We know that the initial amount of salt in the tank is 28 pounds, so
C = 28. Now we just need to find k.
The concentration of salt changes as the pure water flows in and the salt water flows out. So the change in concentration, where y is the concentration of salt in the tank, is 
. Thus, the change in the concentration of salt is found in
inflow of salt - outflow of salt
Pure water, what is flowing into the tank, has no salt in it at all; and since we don't know how much salt is leaving (our unknown, basically), the outflow at 3 gal/min is 3 times the amount of salt leaving out of the 400 gallons of salt water at time t:
Therefore,
or just
and in terms of time,
Thus, our equation is
and filling in 16 for the number of minutes in t:
y = 24.834 pounds of salt
Answer:
B, 140
Step-by-step explanation:
Alright so if you know to do volume this should be a breeze!
First off what you want to do is find the volume of the outside prism.
V=whl=4·5·8=160
160
Then find the smaller prisms volume.
V=whl=1·5·4=20
20
Minus the smaller from the bigger
160-20=140
The answers B!
Answer:
1. No extra fees unless we need out order sooner (2 weeks for an extra $50)
2 .orders of 1000 or more are 40 cents a piece orders of fewer thank 1000 are 60 cents a piece
3. The brochure will arrive in three weeks so we need to pay an extra $50 to get them before the show
Step-by-step explanation:
I’ve done this already but if you need me to explain lmk:)
Its y=3/4x+3
you can solve it
-3x+4y=12
add 3x both sides
4y=3x+12
divide 4 by both sides
y=3/4x+4
A is correct because the f represents the lilies and then you add the 15 because that is how much roses there are going to be. Lastly just multiply the ten that will give you the answer
