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3 years ago

13

Ok this is getting stressful and hard already, we’re not even learning it yet but whatever, please help me will mark Brainliest

if you get it right. I believe in us!

1 answer:

s2008m [1.1K]3 years ago

6 0

Answer:

yes? im pretty sure yeah

Step-by-step explanation:

You might be interested in

In a certain library the first shelf is 15.0 cm off the ground, and the remaining four shelves are each spaced 38.0 cm above the

baherus [9]

Answer:

1747.9 J

Step-by-step explanation:

The work done to lift a book by a certain height $\Delta h$ is

$W=mg\Delta h$

where

m = 1.40 kg is the mass of one book

$g=9.8 m/s^2$ is the acceleration due to gravity

The first shelf is 15.0 cm (0.15 m) from the ground, and it can be filled with 28 books. So, the work done to fill the first shelf is

$W_1=28mg\Delta h=28(1.40)(9.8)(0.15)=57.6 J$

The 2nd shelf is 38.0 cm above the first one, so its height from the ground is

$\Delta h =15.0+38.0 =53.0 cm=0.53 m$

It can also contain 28 books, so the work done to fill this shelf is

$W_2=28 mg\Delta h=28(1.40)(9.8)(0.53)=203.6 J$

The height of the third shelf is

$\Delta h =15.0+38.0 +38.0=91.0 cm=0.91 m$

It can also contain 28 books, so the work done to fill this shelf is

$W_3=28 mg\Delta h=28(1.40)(9.8)(0.91)=349.6 J$

The height of the 4th shelf is

$\Delta h =15.0+38.0 +38.0+38.0=129.0 cm=1.29 m$

It can also contain 28 books, so the work done to fill this shelf is

$W_4=28 mg\Delta h=28(1.40)(9.8)(1.29)=495.6 J$

The height of the 5th shelf is

$\Delta h =15.0+38.0 +38.0+38.0+38.0=167.0 cm=1.67 m$

It can also contain 28 books, so the work done to fill this shelf is

$W_5=28 mg\Delta h=28(1.40)(9.8)(1.67)=641.5 J$

Therefore, the total work done is:

$W=W_1+W_2+W_3+W_4+W_5=57.6+203.6+349.6+495.6+641.5=1747.9 J$

6 0

3 years ago

Enter the value of 5 times (13.5-4.5)

vfiekz [6]

The answer is 45 because you do parenthesis first which is 13.5-4.5=9 then you multiply 9×5=45 therefore the answer is 45.

3 0

3 years ago

Read 2 more answers

elena-14-01-66 [18.8K]

Answer:

C

Step-by-step explanation:

1. Factor a negative one out of the problem.

-1( 7x^2 +5x -18)

2. Factor.

{Factors of 7= 7 &1}

3. (7x ___) (x _____)

Factors of 18= 6,3,18,1,2,9

5 needs to be postive.

5 0

3 years ago

Read 2 more answers

Students took a typing test. The number of words per minute students could type are listed below. 40, 47, 25, 32, 48, 55, 33, 56

const2013 [10]

Answer:

50

Step-by-step explanation:

The median number is known as the middles number

The first step is to rearrange the set of numbers starting from the lowest

25, 32, 32, 32, 33, 40, 47, 47, 48, 55, 56

Hence the middle number is 50

8 0

2 years ago

Idk wat to do.....<br>........

oksano4ka [1.4K]

Answer:

Mean : 95

Median : 85

Mode : 90

Part B : Impossible

Step-by-step explanation:

We can make an equation to find the mean using the first 5 history test scores.

$85=\frac{80+75+90+75+95+n}{6} \\ \\ 85=\frac{415+n}{6} \\ \\ 510=415+n \\ \\ n=95$

So a 95 would be needed to have a mean of 85.

Next, the median.

First, we sort the first 5 history scores from least to greatest.

We get 75, 75, 80, 90, 95.

Since, 80 is the middle value, it will be used in the calculation of the median.

We can make an equation with this.

$82.5=\frac{80+n}{2} \\ \\ 165=80+n \\ \\ n=85$

So a score a 85 would be needed to have a median of 82.5

Thirdly, the mode.

Since 90 is already in the set once, we can just have Maliah score another 90 to make 90 the mode (with the exception of 75 of course).

Finally, Part B.

We can use the equation we had for the first mean calculation but change 85 to 90.

$90=\frac{80+75+90+75+95+n}{6} \\ \\ 90=\frac{415+n}{6} \\ \\ 540=415+n \\ \\ n=125$

So Maliah would need a score of 125 to make her mean score 90, but since the range is only from 0-100, it is impossible.

8 0

3 years ago