help please must be a really quick answer but right!

Answer:

  0.50 seconds

Step-by-step explanation:

The time it takes for an echo to return is the time it takes for the sound to make the round trip between the source and the reflecting object.

The boulder is 80 m away from the source, so the round-trip distance is 2×80 m = 160 m. At a speed of 320 m/s, it takes sound ...

  (160 m)/(320 m/s) = 0.50 s

to make the round-trip.

It will take 0.50 seconds to hear the echo.

The time it will take to hear the echo, when the speed of a sound wave is 320 m/s is 0.50 seconds.

What is the speed of sound?

Speed of sound is the rate by which the sound wave travels. The speed of sound depends on the medium by which the sound wave is travelling.

The speed of the wave can be found out using the following formula.

[tex]s=\dfrac{d}{t}[/tex]

Here, (d) is the distance travelled by the wave and (t) is time taken by the wave to cover that distance.

A boy yells in a narrow valley. The sound reflects off of a boulder that is 80 m away.

For the echo, distance travelled will be doubled as it come back.Thus, the distance travelled by sound wave is,

[tex]d=2\times80\\d=160\rm\; m[/tex]

The speed of sound is 320 m/s. Put these value in the above formula as,

[tex]320=\dfrac{160}{t}\\t=0.5\rm\; s[/tex]

Thus, the time it will take to hear the echo, when the speed of a sound wave is 320 m/s is 0.50 seconds.

Learn more about the speed of sound here;

https://brainly.com/question/95976

[tex]\huge\fcolorbox{blue}{aqua}{Answer:}[/tex]

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[tex] \frac{5}{6}x = 35[/tex]

[tex]x=35\times \left(\frac{6}{5}\right) [/tex]

[tex]x=\frac{35\times 6}{5} [/tex]

[tex]x=\frac{35\times 6}{5} [/tex]

[tex]x=\frac{210}{5} [/tex]

[tex]x=42 [/tex]

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Step-by-step explanation:

#Carry on learning

Answer:

Can u post a picture so I can see what your talking about!?

Answer:

Area of a Rectangular prism is

A = 2lh + 2lw + 2hw

Step-by-step explanation:

See picture above

Answer:

[tex]=7\frac{10}{27}[/tex]

Decimal: 7.37

Step-by-step explanation:

[tex]9\frac{5}{9} -2\frac{5}{27} =\frac{81+5}{9} -\frac{54+5}{27} =\frac{86}{9} -\frac{59}{27}[/tex]

[tex]\frac{258}{27} -\frac{59}{27} =\frac{199}{27}[/tex]

[tex]=7\frac{10}{27}[/tex]

Hope this helps

Answer:

The scale is 11 feet per one inch.

Step-by-step explanation:

[tex]\frac{165feet}{15inches} = 11feet / inch[/tex]

The perimeter of the isosceles right angled triangle whose one leg is of 3 ft is given by: Option C: 6 + 3√2 ft

It has two equal sides, and those two equal sides make 90 degrees (right angle) internally.

Referring to the figure, assuming:

Using the Pythagoras theorem, we get:

[tex]a^2 + a^2 = b^2\\\\a = b/\sqrt{2}[/tex]

It was given that length of one of the leg is of 3 ft. Leg of an isosceles triangle refers to one of its equal sides.

Thus, we got [tex]a = 3[/tex], and therefore, we have: [tex]a = b/\sqrt{2} \implies b = a\sqrt{2} = 3\sqrt{2}[/tex]

Thus, perimeter of the triangle as:

[tex]a + a + b = 2a + b = 6 +3\sqrt{2} \: \rm ft[/tex]

Thus, the perimeter of the isosceles right angled triangle whose one leg is of 3 ft is given by: Option C: 6 + 3√2 ft

Learn more about Pythagoras theorem here:

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Answer:

    C    :    6 + 3√2 ft

Step-by-step explanation:

it is right

trust me

In the case of multiplication in exponents, if the numbers are the same, their exponents are added.

7 + 8 is written to the power of x, and 3 + 2 is written to the power of y.

Answer:

1 positive correlation

2 A

3 negative

Step-by-step explanation:

Hope this helps!:)

Answer:

Assuming they bought the same shoes, $82.5

Step-by-step explanation:

80% of Original Shoe price = $82

Divide by 0.8 to find the original price.

82 / 0.8 = 102.5

102.5-20=82.5

Answer:

2/5 > 1/4

Step-by-step explanation:

First convert the denominators to the LCM which will be 20

2/5 will convert to 8/20 because 5 x 4 = 20 so 2 x 4 = 8 and 1/4 will convert to 5/20 because 4 x 5 = 20 so 1 x 5 = 5

The straw is placed diagonally in the rectangular prism, therefore, the length of the straw is √109 inches

Diagonal of a rectangular prism = √(l² + w² + h²)

Where,

Therefore,

l = 6 inches

w = 3 inches

h = 8 inches

diagonal = √(6² + 3² + 8²)

diagonal = √36 + 9 + 64

diagonal = √109 inches

learn more rectangular prism here:https://brainly.com/question/21888893

82 = 0.82 = multiplier

134.18 x 0.82 = 110.0276

= £110.03 (2.d.p)

Answer:

  (d)  0.8736

Step-by-step explanation:

Unless you have a table of the normal distribution available, this is a calculator problem. Your calculator, or any spreadsheet, can tell you the probability is ...

  P(-1.23 ≤ z ≤ 2.12) ≈ 0.8736

All three are similar

In ∆SUT and ∆VWX

So by SSA they are similar

In ∆PRQ and rest two

All angles are.

So

They are similar by AAA congruence

Answer:

c = 2.5 , d = - 3

Step-by-step explanation:

f(x) = cx + d

f(4) = 7 ( substitute x = 4 into the equation and equate to 7 )

f(10) = 22 ( substitute x = 10 into the equation and equate to 22 )

4c + d = 7 → (1)

10c + d = 22 → (2)

subtract (1) from (2) term by term to eliminate d

(10c - 4c) + (d - d) = 22 - 7 , that is

6c = 15 ( divide both sides by 6 )

c = 2.5

substitute c = 2.5 into (1) and solve for d

4(2.5) + d = 7

10 + d = 7 ( subtract 10 from both sides )

d = - 3

Answer:

c = 2.5

d = - 3

Step-by-step explanation:

f(x) = cx + d

f(4) = 7

f(10) = 22

4c + d = 7

10c + d = 22

(10c - 4c) + (d - d) = 22 - 7

6c = 15

---    ----

6      6

c = 2.5

4(2.5) + d = 7

10 + d = 7

-10       -10

d = - 3

Answer:

Step-by-step explanation:

When the stick hits the ground it has the height of zero.

Substitute h with 0 and solve the given equation for t:

[tex]- 16t^2 + 95 = 0\\16t^2 = 95\\t^2 = 95/16\\t = \sqrt{5.93} \\t=2.44[/tex]

well, since we know the diameter points, half-way in between is the center

[tex]~~~~~~~~~~~~\textit{middle point of 2 points } \\\\ (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-1})\qquad (\stackrel{x_2}{-25}~,~\stackrel{y_2}{-11}) \qquad \left(\cfrac{ x_2 + x_1}{2}~~~ ,~~~ \cfrac{ y_2 + y_1}{2} \right) \\\\\\ \left(\cfrac{ -25 -1}{2}~~~ ,~~~ \cfrac{ -11 -1}{2} \right)\implies \left(\cfrac{-26}{2}~~,~~\cfrac{-12}{2} \right)\implies (-13~~,~~-6)[/tex]

and its radius will be half the length of the diameter

[tex]~~~~~~~~~~~~\textit{distance between 2 points} \\\\ (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-1})\qquad (\stackrel{x_2}{-25}~,~\stackrel{y_2}{-11})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ d=\sqrt{[-25 - (-1)]^2 + [-11 - (-1)]^2}\implies d=\sqrt{(-25+1)^2+(-11+1)^2} \\\\\\ d=\sqrt{(-24)^2+(-10)^2}\implies d=\sqrt{676}\implies d=26~\hfill \stackrel{half~that}{r=13}[/tex]

[tex]\rule{34em}{0.25pt}\\\\ \textit{equation of a circle}\\\\ (x- h)^2+(y- k)^2= r^2 \qquad center~~(\stackrel{-13}{ h},\stackrel{-6}{ k})\qquad \qquad radius=\stackrel{13}{ r} \\\\[-0.35em] ~\dotfill\\\\\ [x-(-13)]^2~~ + ~~[y-(-6)]^2~~ = ~~13^2\implies (x+13)^2~~ + ~~(y+6)^2~~ = ~~169[/tex]

Step-by-step explanation:

let kevein be x and daniel be y

x=4y (equation i)

x=6+y(equationii)

putting the value of x in equationii

4y=6+y

3x=6

x=2

Answer:

slope = 0.5

Step-by-step explanation:

[tex]slope=\frac{-5-1}{-6-6} =\frac{-6}{-12} =\frac{1}{2} =0.5[/tex]

Hope this helps

The slope of the graph through points (6,1) and (-6,-5) is 0.5.

The slope formula can be expressed as:

[tex]Slope (m) = \frac{y_2 - y_1}{x_2 - x_1}[/tex]

Given the coordinates of the points through which the graph passes through:

Point 1 ( 6,1 )

x₁ = 6

y₁ = 1

Point 2( -6,-5 )

x₂ = -6

y₂ = -5

Plug the coordinates into the slope formula and simplify.

[tex]Slope (m) = \frac{y_2 - y_1}{x_2 - x_1}\\\\Slope (m) = \frac{-5 - 1}{-6 - 6}\\\\Slope (m) = \frac{-6}{-12}\\\\Slope (m) = \frac{1}{2}\\\\Slope (m) = 0.5[/tex]

Therefore, the slope of the line is 0.5.

Learn more about slope formula here: brainly.com/question/24578307

#SPJ3

Answer: Best answer gets brainliest!

Step-by-step explanation:

Add the amount of students together!

Hopefully this helps you!

-Keira

First, let's check how many 7th grade students take the bus.

On the graph, find "7th grade"

There are 90 7th grade students taking the bus.

Same with the 8th grade:-

120 students

How many 7th & 8th grade students take the bus?

The sum of the 7th grade students & the 8th grade students is your answer.

So, add:-

[tex]\sf{90+120}[/tex]

[tex]\bigstar{\boxed{\pmb{210~students}}\longleftarrow\sf{Option~B~is~correct}}}[/tex]

Hope everything is clear; if you need any explanation/clarification, kindly let me know, and I'll comment and/or edit my answer :)

Answer:

Rhombi and Squares

Step-by-step explanation:

1) KY (pythagorean Thm) 5² + x² = 13²    ...= 12

2) PK Diagonals bisected. also = 12

3) Diagonals of rhombi are perpendicular. <YKZ = 90

4) 67. Alternate interior angles are congruent.

5) 3. Diagonals are bisected and congruent for squares.

6) 45° . Angles are bisected by diagonals.

7) 90° . All angles of squares are right angles.

8) 6. Diagonals are bisected. So 3 is doubled to 6.

9) I need graph paper.. hol'up

Answer:

The answer is 1.25

Step-by-step explanation:

5% of 25 = ?

5/100 × 25

1/20 × 25 = 25/20 = 5/4 = 1.25

Thus, 5% of 25 is 1.25

Answer:

-1 7/10

Step-by-step explanation:

Hope that helps!!!

Answer: C

Step-by-step explanation:

They are substituting PQ=25 from steps 1 and 3.

Answer:

I belive the answer is 96 ft.

Step-by-step explanation:

Hope that helps!

The statement that is true about trend lines is: A. A trend line should be as close as possible to the points.

A trend line, which can also be called the line of best fit, is a straight line that represents the pattern of a data, which can be positive or negative.

A trend line does not necessarily need to connects all the points, but goes through some points to show the pattern. It may not even be necessary to go through any of the points, what's improtant is for the trend line to be close to as many points as possible.

Therefore, the statement that is true about trend lines is: A. A trend line should be as close as possible to the points.

Learn more about trend lines on:

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