<span>If you give it a good search, the most used answer would probably be as follows,
</span><span>In 1914 Henry Moseley found a relationship between an element's X-ray wavelength and its atomic number (Z), and therefore rearranged the table by nuclear charge / atomic number rather than atomic weight. Before this discovery, atomic numbers were just sequential numbers based on an element's atomic weight. Moseley's discovery showed that atomic numbers had an experimentally measurable basis.
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Hope this helps!
The answer is A. planning a hiking trip
A topographical map would not help studying plant growth over time unless you are looking for a better altitude to plant said plants.
A topographical map would not help studying rainfall for one year unless your location was <em>really</em> so high or low that it affected your weather
And most of all, a topographical map would not be useful for planning a cuise across the Atlantic Ocean because the elevation of the sea is zero!
A topographical map <em>would</em> be useful for planning a hiking trip because there are many factors and details that a hike should have. Which includes height, distance, paths, and elevation.
The PH of water is 7 because it contains an equal amount of h and oh- ions.
I think it is a radiation poisoning