Atomic mass of helium is 4.002642g/mol
(542000g)/(4.002642g/mol)*6.02*10^23 = 8.15*10^28 atoms
They are colourless solids (salts) that do not conduct electricity when solid, but conduct electricity in aqueous solution as the ions (that carry charge) are free to move.
They have a high melting point due to the strong electrostatic forces of attraction between oppositely charged ions
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iE xplanation:am osrry nisot p ake inligsh
The hydrosphere brings water to the human environment. <span />
Answer:
1. hot 2. night 3. mammals (not completely sure about this one)
Explanation: