Someone please help me with these questions! (The ones in the picture) Please I am super confused!

Study the following reaction carefully. what classification should this reaction have? 4al + 3o2 2al2o3synthesisdecompositionsingle replacementdouble displacement

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy

Find v1, the speed of the fluid in the left end of the main pipe. express your answer in terms of h1, h2, g, and either a1 and a2 or γ, which is equal to a1a2.