Is an aluminum plate a mixture of solids, element, suspension, compound, or an alloy?

Describe the chemical reaction based on the chemical equation below. also, explain whether the equation is balanced.

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?

Ajet plane is speeding down the runway during takeoff. air resistance is not negligible. identify the forces on the jet.