The acceleration of the bookshelf is equal to 1.30 
<u>Given the following data:</u>
- Mass of bookshelf = 51.5 kilogram
To determine the acceleration of the bookshelf, we would apply Newton's Second Law of Motion:
Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on the object while being inversely proportional to its mass.
Mathematically, Newton's Second Law of Motion is given by this formula;

Substituting the given parameters into the formula, we have;

Acceleration = 1.30 
Read more on net force here: brainly.com/question/1121817
![\bf \begin{array}{lllll} round(x)&\boxed{1}&2&3&\boxed{4}\\\\ wrestlers[f(x)]&\boxed{64}&32&18&\boxed{9} \end{array} \\\\\\ slope = {{ m}}= \cfrac{rise}{run} \implies \cfrac{{{ f(x_2)}}-{{ f(x_1)}}}{{{ x_2}}-{{ x_1}}}\impliedby \begin{array}{llll} average\ rate\\ of\ change \end{array}\\\\ -------------------------------\\\\ f(x)= \qquad \begin{cases} x_1=1\\ x_2=4 \end{cases}\implies \cfrac{f(4)-f(1)}{4-1}\implies \cfrac{9-64}{4-1}\implies \cfrac{-55}{3}](https://tex.z-dn.net/?f=%5Cbf%20%5Cbegin%7Barray%7D%7Blllll%7D%0Around%28x%29%26%5Cboxed%7B1%7D%262%263%26%5Cboxed%7B4%7D%5C%5C%5C%5C%0Awrestlers%5Bf%28x%29%5D%26%5Cboxed%7B64%7D%2632%2618%26%5Cboxed%7B9%7D%0A%5Cend%7Barray%7D%0A%5C%5C%5C%5C%5C%5C%0Aslope%20%3D%20%7B%7B%20m%7D%7D%3D%20%5Ccfrac%7Brise%7D%7Brun%7D%20%5Cimplies%20%0A%5Ccfrac%7B%7B%7B%20f%28x_2%29%7D%7D-%7B%7B%20f%28x_1%29%7D%7D%7D%7B%7B%7B%20x_2%7D%7D-%7B%7B%20x_1%7D%7D%7D%5Cimpliedby%20%0A%5Cbegin%7Barray%7D%7Bllll%7D%0Aaverage%5C%20rate%5C%5C%0Aof%5C%20change%0A%5Cend%7Barray%7D%5C%5C%5C%5C%0A-------------------------------%5C%5C%5C%5C%0Af%28x%29%3D%20%20%20%5Cqquad%20%0A%5Cbegin%7Bcases%7D%0Ax_1%3D1%5C%5C%0Ax_2%3D4%0A%5Cend%7Bcases%7D%5Cimplies%20%5Ccfrac%7Bf%284%29-f%281%29%7D%7B4-1%7D%5Cimplies%20%5Ccfrac%7B9-64%7D%7B4-1%7D%5Cimplies%20%5Ccfrac%7B-55%7D%7B3%7D)
55 over 3, or 55 wrestlers for every 3 rounds, but the wrestlers value is negative, thus 55 "less" wrestlers for every 3 rounds on average.
To find the expected value of the distribution, we multiply each outcome by it's probability. Doing this, we get that the expected value of defects on a skateboard is of
.
Outcomes and probabilities:
0 defects, 9/10 probability
1 defect, 1/20 probability
2 defects, 1/25 probability
3 defects, 1/100 probability.
Expected value:

Dividing both numerator and denominator by 4:

Thus, the expected value of defects on a skateboard is of
.
A similar problem is given at: brainly.com/question/23156292.
<h3>
Answer: D) One solution</h3>
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Work Shown:
2(b+3)-17 = 3b-7+b
2b+6-17 = 4b-7
2b-11 = 4b-7
-11+7 = 4b-2b
-4 = 2b
2b = -4
b = -4/2
b = -2
There is one solution and it is b = -2
A quick way to tell we have one solution is to note that both sides are a linear expression, and that the slopes of each linear expression are different values. If you had two lines with the same slope, then you'd have either parallel lines or coinciding lines (leading to no solutions and infinitely many solutions respectively). When you have two lines with two different slopes, then they are guaranteed to intersect only once. That intersection point is the solution.