How does smog affect landforms, like valleys, plains etc

Pentane with molecular formula c5h12, exists in three isomeric forms. one shows linear carbon chains, another has one -ch3 groups present on the third carbon atom, and the third has two -ch3 groups present on the second carbon atom. what types of isomers are these? a. geometric isomers b. structural isomers c. halotropic isomers

Pulmonary arteries carry highly oxygenated blood. true or false?

What do all celular activities in living organisms use as a source of energy?