<span>A.H2O = water, so it is a liquid at room temperatures (melting point = 0C) and melting point must be below 20C
B.HCl = A gas at room temperatures, so melting point (-114C) is definitely lower than 20C.
Melting points of the aqueous solution (solution in water) at different concentrations are all below that of water, i.e. 0C.
C.CH4 = A gas at room temperatures, so melting point (-182C) must be below 20C.
D.MgCl2 = A white powdery solid at room temperatures, so its melting point (714C) must be above 20C (So this is the only one among the four choices that melts above 20 ° C).</span>
Answer: 35.4 degrees
Explanation: because it cold
The rule is number your table 1 2. 3 4 5 6 7 0 the number of shells increase as you go further up as it indicates the number of electrons on the outer shell e.g Argon will have 3 electrons on its outer shell hope this helps if not its then tighttt
