It means every thing is made out of Atoms and some things are element componds so elements are the "backbone" of the compounds.
Construct a vector diagram. It will be a right-angled triangle. One vector (the hypotenuse) represents the heading of the boat, one represents the current and one represents the resultant speed of the boat, which I'll call x. Their magnitudes are 20, 3 and x. Let the required angle = theta. We have:
<span>theta = arcsin(3/20) = approx. 8.63° </span>
<span>The boat should head against the current in a direction approx. 8.63° to the line connecting the dock with the point opposite, or approx. 81.37° to the shore line. </span>
<span>x = sqrt(20^2 - 3^2) </span>
<span>= sqrt(400 - 9) </span>
<span>= sqrt 391 </span>
<span>The boat's crossing time = </span>
<span>0.5 km/(sqrt 391 km/hr) </span>
<span>= (0.5/sqrt 391) hr </span>
<span>= approx. 0.025 hr </span>
<span>= approx. 91 seconds</span>
1. Physical size of Russia compared to other countries, despite a lack of visible borders from space.
2. Part of Russia's outline would likely be obscured by the various clouds and objects in the stratosphere; this would allow the astronaut to view potential cloud and weather patterns on earth.
3. An astronaut could see outlines of Russia's geography such as mountain ranges.
Hope that it helps :)
Are you referring to the fact that water is a compound while hydrogen is an element? If I'm wrong just comment and clarify and I can edit it, I don't even know what kind of unit you're in. :)
Answer : The angle between the string and the horizontal is 30 degrees
Explanation: Imagine this a a triangle where the length of the string (200m) is the hypotenuse and the height of the kite is the opposite side (100m) .
Let the angle between the string and the horizontal be theta.
Now sin (Theta) = opposite side/hypotenuse
= 100/200 = 1/2
Therefore Theta = Sin ⁻¹ ( 1/2 )
Theta = 30 degrees