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.
The population in the above situation is the total number of students under Mr. Wilson.
A sample is a part of the population that may best represent the population. There is no sample in the above situation because Mr. Wilson made all students pick 5 note cards. He will be able to determine the performance of each student based on their performance in picking 5 note cards and defining the terms in each card.
Answer:
Step-by-step explanation:
Given x^2+4x+13=0, find the complex roots. The best approach here is to use the quadratic formula. Note that a = 1, b = 4 and c = 13.
Thus, the discriminant, b^2 - 4ac, is (4)^2 - 4(1)(13) = 16 - 52 = -36, and the square root of that is plus or minus i√36, or plus or minus 6i.
plus or minus i√
Answer:
(-4, 8)
Step-by-step explanation:
