Given:
Total solution : 1000mL
Pure acetic acid = 26mL
To find:
The percent concentration of given solution.
Solution:
We know that,

Putting the given values, we get



Therefore, the percent concentration of this solution is 2.6%.
Answer:
As per the statement:
The path that the object takes as it falls to the ground can be modeled by:
h =-16t^2 + 80t + 300
where
h is the height of the objects and
t is the time (in seconds)
At t = 0 , h = 300 ft
When the objects hit the ground, h = 0
then;
-16t^2+80t+300=0
For a quadratic equation: ax^2+bx+c=0 ......[1]
the solution for the equation is given by:

On comparing the given equation with [1] we have;
a = -16 ,b = 80 and c = 300
then;


Simplify:
= -2.5 sec and
= 7.5 sec
Time can't be in negative;
therefore, the time it took the object to hit the ground is 7.5 sec
Answer: A. 
B. A'(5) = 1.76 cm/s
Step-by-step explanation: <u>Rate</u> <u>of</u> <u>change</u> measures the slope of a curve at a certain instant, therefore, rate is the derivative.
A. Area of a circle is given by

So to find the rate of the area:


Using 

Then
![\frac{dA}{dt}=2.\pi.r.[\frac{726}{(t+11)^{3}}]](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.r.%5B%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D%5D)
![\frac{dA}{dt}=2.\pi.[3-\frac{363}{(t+11)^{2}}].\frac{726}{(t+11)^{3}}](https://tex.z-dn.net/?f=%5Cfrac%7BdA%7D%7Bdt%7D%3D2.%5Cpi.%5B3-%5Cfrac%7B363%7D%7B%28t%2B11%29%5E%7B2%7D%7D%5D.%5Cfrac%7B726%7D%7B%28t%2B11%29%5E%7B3%7D%7D)
Multipying and simplifying:

The rate at which the area is increasing is given by expression
.
B. At t = 5, rate is:




At 5 seconds, the area is expanded at a rate of 1.76 cm/s.
If a secant<span> and a </span><span>tangent of a circle </span><span>are drawn from a point outside the circle, then the product of the lengths of the secant and its external segment equals the square of the length of the tangent segment.
</span><span>
y</span>² = 7(15+7)
<span>y</span>² = 7*22
<span>y</span>² = 154
<span>y = </span>√154
<span>y = 12.4 </span>← to the nearest tenth<span>
</span><span>
</span>
Answer:
48
Step-by-step explanation:
2500 - 196 = 
x = 48
Please mark as brainliest for future answers :)