PLEASE HELP again I’m really bad at this :)

An excess of lithium oxide undergoes a synthesis reaction with water to produce lithium hydroxide li2o+h2o→2lioh if 1.05 g of water reacted, what is the theoretical yield of lithium hydroxide? a) 5.83 x 10–2 g lioh b) 1.17 x 10–1 g lioh c) 2.79 x 100 g lioh d) 1.40 x 100 g lioh

At stp, which substance is the best conductor of electricity? a. nitrogen b. neon c. sulfur d. silver

Which of these are physical changes in matter? check all that apply boiling water a pencil being sharpened exploding dynamite freezing water rotting cheese