The two are potassium and rubidium. Why? Na is an alkali metal. As you go down the metals become more reactive.
Calcium has 20 protons. Why? The atomic # is 20 (the one at the top).
It has 20 neutrons. Why? The atomic mass (the number on the bottom) is ~40, ignoring electron mass. 40- 20 protons = 20 neutrons.
It has 20 electrons.
Why? The # of protons and electrons is the same. Ions aren't on the periodic table.
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Answer:
What is the main advantage to using satellites to measure climate change?
Explanation:
answer A...Satellites in a low earth orbit can directly monitor the climate from their position within or just above the atmosphere, and can provide near-global coverage as they scan over different swathes of ground with each orbit.
I think it wouldn’t be dead until it looses all of its color and is able to crumple in your fingertips. So basically, it isn’t dead yet when it is wilted. But Its getting to the stage of being dead (like how old people are at that stage of their life where they will pass away soon).
To put it simply, the flower is not dead yet, it’s just “old” :D
One type of landform formed by wind would be sanddunes. This is the only landform I can think of formed by wind. The wind blows the sand along so that it builds up into a dune perhaps when it hits an obstacle like a small rocky spur and whole deserts can be converted into dunes.