Answer:
(B) 
General Formulas and Concepts:
<u>Calculus</u>
Limits
Derivatives
- The definition of a derivative is the slope of the tangent line.
Derivative Notation
Instantaneous Rates
- Tangent Line:

Step-by-step explanation:
Since we are trying to find a <em>rate</em> at which W(t) changes, we must find the <em>derivative</em> at <em>t</em> = 3.
We are given 2 close answer choices that would have the same <em>numerical</em> answer but different <em>meanings</em>:
- (A)

- (B)

If we look at answer choice (A), we see that our units would simply just be volume. It would not have the units of a rate of change. Yes, it may be the closest numerically correct answer, but it does not tell us the <em>rate</em> at which the volume would be changing and it is not a derivative.
If we look at answer choice (B), we see that our units would be cm³/s, and that is most certainly a rate of change. Answer choice (B) is also a <em>derivative</em> at <em>t</em> = 3, and a derivative tells us what <em>rate</em> something is changing.
∴ Answer choice (B) will give us the best estimate for the value of the instantaneous rate of change of W(t) when <em>t</em> = 3.
Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Differentiation
Book: College Calculus 10e
Answer:
x is mL of 25% acid and y is mL of 50% acid
We set up 2 equations:
A) x + y = 250
B) .25 x + .50y = .35 * 250 which equals
B) .25x + .50y = 87.50 Multiplying A) by -.5
A) -.5x -.5y = -125 adding the equations we get
-.25x = -37.50
x = 150 mL
y = 100 mL
Source: http://www.1728.org/mixture.htm
Step-by-step explanation:
change to improper fraction:
22 4/5
22*5=110+4=114
114/5
divide:
114/5=22.8
Thus, 22 4/5 as a decimal is 22.8