Answer:
Step-by-step explanation:
Given that a large mixing tank initially holds 400 gallons of water in which 70 pounds of salt have been dissolved. Pure water is pumped into the tank at a rate of 4 gal/min, and when the solution is well stirred, it is then pumped out at the same rate.
Let Q(t) be the quantity of salt at time t.
Q(0) = 70 pounds
Inflow of water = outflow = 4 gal/min
So resulting volume of tank at time t = 400 gallons
Rate of change of salt = inflow - outflow
= 0 - 
i.e. 
This is a variable separable equation
Use when t =0 Q = 70
A =70
So A(t) = Q(t) = 
and
A(0) = Q(0) = 70 lbs.
Answer:
$12.60
Step-by-step explanation:
42/30%=42/0.3=$12.60
Brainleist plz
(comment if spelling is wrong anywhere)
Set up an equation 20=k(0.4)....to find k divide 20 by 0.4
First, divide the shape into two figures ( a semicircle and a rectangle)
Then, find the are or the two shapes using the area formula for a semicircle (
) and the are formula for a rectangle (base x height)
Finally, add the two areas together and you have your answer
Answer:
Step-by-step explanation:
We are given that
By ohm's law
R=389 ohm
I=0.03 A
We have to find rate of change of current I means 
Differentiate the equation w.r.t t
Substitute the values then we get
Hence, the current I is changing at the rate=-0.00016A/s
