Answer:
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Krypton is a colorless, odorless gas. It has a boiling point of -152.9°C (-243.2°F) and a density of 3.64 grams per liter. That makes krypton about 2.8 times as dense as air.
Explanation:
i think its B)... im not sure so dont take it seriously
The answer is 4.0 m
Yes, if θ = 45°