A mixture contains salt, sand, pebbles, and grass. Which part of this mixture is soluble in water?

With i really need the correct answer!

Select all the correct answers. which changes will increase the rate of reaction during combustion? decreasing the area of contact between the reactants adding more oxygen to the reaction removing heat from the reaction changing the reactants from solid form to powdered form lowering the exposure of the reactants to air

Which if these is an etiquette rule? (american football) question 10 options: a. debating with the ref over a call b. not communicating with your team c. post-game handshake d. taunting