6x10^8 kg<br> —————<br> 2x10^4 m^3

The acclaimed environmental book, Silent Spring, was written by this woman in 1962.

olga_2 [115]

Rachel Carson was the author of the acclaimed environmental book, Silent Spring. The book was published in 1962.
It documented the negative effect that synthetic pesticides have on the environment, specifically on birds.
This book laid bare to the American public what chemical companies indirectly contributed to the environment.
The public furor this book caused led to the reversal of the national pesticide policy, a nationwide ban on DDT for agricultural uses, and inspired the creation of the U.S. Environmental Protection Agency.

7 0

3 years ago

Use the drop-down menus to identify the parts of DNA. Label A: Label B:

love history [14]

Label A:

Nitrogen bases

Label B:

Sugar-phosphate backbone

7 0

3 years ago

Read 2 more answers

A double concave lens is a ________ lens, and a double convex lens is a ______ lens.

forsale [732]

Answer:

b. diverging, converging

4 0

3 years ago

A ski lift has a one-way length of 1 km and a vertical rise of 200 m. The chairs are spaced 20 m apart, and each chair can seat

RSB [31]

Answer:

Explanation:

The question states that the chairs are spaced 20 m apart through a length of 1 km, or say, 1000 m.

It also does say that each chair weighs 250 kg, and as such the load is

M = 50 * 250

M = 12500.

Taking into consideration, the initial and final heights, we have

h1 = 0, h2 = 200 m

The work needed to raise the chairs,

W = mgh, where h = h2 - h1

W = 12500 * 9.81 * (200 - 0)

W = 2.54*10^7 J

The work is done at a rate of 10 km/h, and at a distance of 1 km, time taken would be

t = 1/10 = 0.1 h or say, 360 s

The power needed thus, is

P = W/t

P = 2.54*10^7 / 360

P = 68125 W, or 68 kW

Initial velocity, u = 0 m/s

Final velocity, v = 10 km/h = 2.78 m/s

Startup time, t is 17 s

Acceleration during the startup then is

a = (v - u)/t

a = 2.78/17

a = 0.163 m/s²

The power needed for the acceleration is

P = ½m [(v² - u²)/t]

P = ½ * 12500 * [2.78²/17]

P = 6250 * 0.455

P = 2844 W

3 0

3 years ago

A block floats partially submerged in a container of liquid. When the entire container is accelerated upward, which of the follo

Nookie1986 [14]

Answer:C

Explanation:

Partially submerged block along with vessel is accelerated upwards .

Initially the block weight is supported by buoyant force such that it is in equilibrium.

when the system start accelerating upwards then the effective gravity will be

g+a where a is the acceleration of the system.

so only net gravity is increased so block will not ascend or descend.

Mathematically

$F_b=weight$

$\rho _L\cdot V\cdot (g+a)=m(g+a)$

where $\rho _L=$ density of liquid

V=volume of object inside the water

7 0

3 years ago

6x10^8 kg ————— 2x10^4 m^3