<span>Magnesium????
i hope this helps
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A or B depends on what you mean by lit or glowing but when you place a wooden split in the sample the gas must reignite but there can be some confusion between hydrogen and oxygen mainly because a splint can cause a slight popping sound while it reignites but hydrogen pops are more violent and can most time extinguish the splint.
Answer:
The correct option is methane :
.
Explanation:
Average speed of the gas molecules id given by expression:

k = Boltzmann cosnatnt
T = Temperature of the gas molecules = 355 K
m = molecular mass of the molecule

Molar mass of methane = 18 g/mol
Molar mass of neon = 20.18 g/mol
Molar mass of ethene = 28 g/mol
Molar mass of chlorine gas = 70 g/mol
Lower the value of molar mass of gas molecule higher will be the average speed.So, from the given options methane gas greatest average seed because it has lowest molecular mass
Answer:
Explanation By looking at past concentrations of greenhouse gasses in layers in ice cores, scientists can calculate how modern amounts of carbon dioxide and methane compare to those of the past, and, essentially, compare past concentrations of greenhouse gasses to temperature. Ice coring has been around since the 1950s.n: