An earthworm and a snake both possess which o the following characteristics?
(A) Radial symmetry
(B) Dorsal tubular nervous system
(C) Closed circulatory system
(D) Chitinous exoskeleton
(E) Scales

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