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3 years ago

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The height of a street light is 25 feet. It casts a 20−foot shadow. At the same time, a man standing next to the street light ca

sts a 5−foot shadow. How tall is the man? If needed, round the answer to the nearest hundredth.

1 answer:

Sergio039 [100]3 years ago

8 0

The man would be 6 fooot

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use the poisson distribution to find the indicated probability. if the random variable x has a poisson distribution with mean of

Hitman42 [59]

$P(X=2)=\frac{e^{-6} 6^{2}}{2}=0.045$

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3 years ago

How can i get the answer to 5 X 70 = 5 X ____ tens = ____ tens = _____

Maru [420]

Multiple 5x70 to get 350. Which makes the equation 350=5x and then you have to divide both sides by 5 to get x by itself. so 5x/5 and 350/5 makes x=70

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3 years ago

A cube made of an unknown material has a height of 9 cm. The mass of this cube is 3.645 grams. What is the density of this cube?

ehidna [41]

Answer:

$density = \frac{mass}{volume}$

mass = 3.645 g

volume = 9×9×9

= 729 cm³

density = 3.645/729

= 0.005 gcm^-3

Step-by-step explanation:

the volume is 729 cm³ cause the given height is 9cm and it is a cube. cube has equal sides so their lengths are the same.

volume = length × height × width

8 0

3 years ago

Evaluate the surface integral S F · dS for the given vector field F and the oriented surface S.

sweet-ann [11.9K]

Answer:

2.794

Step-by-step explanation:

Recall that if G(x,y) is a parametrization of the surface S and F and G are smooth enough then

$\bf \displaystyle\iint_{S}FdS=\displaystyle\iint_{R}F(G(x,y))\cdot(\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y})dxdy$

F can be written as

F(x,y,z) = (xy, yz, zx)

and S has a straightforward parametrization as

$\bf G(x,y) = (x, y, 3-x^2-y^2)$

with 0≤ x≤1 and 0≤ y≤1

So

$\bf \displaystyle\frac{\partial G}{\partial x}= (1,0,-2x)\\\\\displaystyle\frac{\partial G}{\partial y}= (0,1,-2y)\\\\\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y}=(2x,2y,1)$

we also have

$\bf F(G(x,y))=F(x, y, 3-x^2-y^2)=(xy,y(3-x^2-y^2),x(3-x^2-y^2))=\\\\=(xy,3y-x^2y-y^3,3x-x^3-xy^2)$

and so

$\bf F(G(x,y))\cdot(\displaystyle\frac{\partial G}{\partial x}\times\displaystyle\frac{\partial G}{\partial y})=(xy,3y-x^2y-y^3,3x-x^3-xy^2)\cdot(2x,2y,1)=\\\\=2x^2y+6y^2-2x^2y^2-2y^4+3x-x^3-xy^2$

we just have then to compute a double integral of a polynomial on the unit square 0≤ x≤1 and 0≤ y≤1

$\bf \displaystyle\int_{0}^{1}\displaystyle\int_{0}^{1}(2x^2y+6y^2-2x^2y^2-2y^4+3x-x^3-xy^2)dxdy=\\\\=2\displaystyle\int_{0}^{1}x^2dx\displaystyle\int_{0}^{1}ydy+6\displaystyle\int_{0}^{1}dx\displaystyle\int_{0}^{1}y^2dy-2\displaystyle\int_{0}^{1}x^2dx\displaystyle\int_{0}^{1}y^2dy-2\displaystyle\int_{0}^{1}dx\displaystyle\int_{0}^{1}y^4dy+\\\\+3\displaystyle\int_{0}^{1}xdx\displaystyle\int_{0}^{1}dy-\displaystyle\int_{0}^{1}x^3dx\displaystyle\int_{0}^{1}dy-\displaystyle\int_{0}^{1}xdx\displaystyle\int_{0}^{1}y^2dy$

=1/3+2-2/9-2/5+3/2-1/4-1/6 = 2.794

5 0

3 years ago

if U={natural number less than 10}, M={multiples of 2}, N={factors of 8} and O={even number} then can we write M intersection (N

mr_godi [17]

Answer:

yes

Step-by-step explanation:

u={1,2,3,4,5,6,7,8,9}

m={2,4,6,8}

N={1,2,4,8}

O={2,4,6,8}

Now

M intersection (N intersection O) = (M intersection N) intersection O

or , {2,4,6,8} intersection {2,4,8} ={2,4,8}

intersection {2,4,6,8 }

:. {2,4,8} ={2,4,8}

7 0

3 years ago