Because of their different longitude.
Answer: The Gregorian calendar month, which is 1⁄12 of a tropical year, is about 30.44 days, while the cycle of lunar phases (the Moon's synodic period) repeats every 29.53 days on average. Therefore, the timing of the lunar phases shifts by an average of almost one day for each successive month.
Explanation: This is what GOOGLE says
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The concentration of a cell is generally 0.15 M (0.9 % NaCl)
As given the solution has concentration = 200mm = 0.02 M
This concentration of solution is less than the concentration of cell
Hence solution is hypotonic (less concentration) and cell will be hypertonic
Explanation:
Sodium has atomic number of 11 and its electronic configuration is given by:
![[Na]=1s^22s^22p^63s^1](https://tex.z-dn.net/?f=%5BNa%5D%3D1s%5E22s%5E22p%5E63s%5E1)
The nearest stable electronic configuration to sodium is of the neon. So, in order to attain stability of noble gas it will loose its single electron.

![[Na^+]=1s^22s^22p^63s^0](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D1s%5E22s%5E22p%5E63s%5E0)
Sodium has single valency that is 1.
Let nbe the valency of the ion 'X'
By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the formulas for all the possible compounds that sodium can form with the other ions will be:
