How do you time travel?

Waves that cause the most damage during an earthquake are a. surface waves c. s waves b. p waves d. ocean waves

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On a day when the barometer reads 75.23 cm, a reaction vessel holds 250 ml of ideal gas at 20 celsius. an oil manometer ( ρ= 810 kg/m^3) reads the pressure in the vessel to be 41 cm of oil and below atmospheric pressure. what volume will the gas occupy under s.t.p.?