What volume of 0.475M hydrochloric acid is needed to create 500 mL solution of 0.250 M

Harry lives in a city, and he has a lung condition known as asthma. on certain days, harry has to stay inside because pollutants in the air make it difficult for him to breathe. which of these pollution sources are nonpoint sources that might bother harry if he goes outside? choose the two that apply.

Which scientists contributed to the determination of how cfcs in clouds in the upper atmosphere could destroy ozone molecules

The bone of a dinosaur and the imprint of a leaf are examples of which kind of fossils? a) index b) body c) amber d) trace