Fossils of lobe-finned fishes, which are ancestors of amphibians, are found in rocks that are at least 380 million years old. Fossils of the oldest amphibian-like vertebrate animals with true legs and lungs are found in rocks that are approximately 363 million years old. Three samples of rocks are available that might contain fossils of a transitional species between lobe-finned fishes and amphibians: one rock sample that is 350 million years old, one that is 370 million years old, and one that is 390 million years old. (a) Select the most appropriate sample of rocks in which to search for a transitional species between lobe-finned fishes and amphibians. Justify your selection. (b) Describe TWO pieces of evidence provided by fossils of a transitional species that would support a hypothesis that amphibians evolved from lobe-finned fishes.

(a) The most appropriate sample of rocks in which to search for a transitional species between lobe-finned fishes and amphibians is the one that is 370 million years old.  

(b)  Extremities´ bones and inner ear.

Explanation:  

(a) Lobe-finned fishes are ancestors of amphibians, and their fossils are found in rocks that are at least 380 million years old. On the other hand, the oldest amphibian-like vertebrate animals with true legs and lungs are found in rocks that are approximately 363 million years old. According to this information:

(b)

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.