How much heat, in kilojoules, is needed to raise the temperature of 236 g of silver from 8.5oC to 34.9 °C? (cAg = 0.24 J/g°C)

Iknow the answer is a but i don't know why

Smog is the term used to describe the combination of fog and smoke

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