4) what is an unconformity? where can you find one in the grand canyon? what types of rocks contact at the "great unconformity," and about how old is each type of rock? what does the missing time between the two rock formations mostly likely represent? explain in 3-5 sentences

a surface of contact between two groups of unconformable strata.

"erosion beneath the Hercynian unconformity has removed most of the Westphalian strata"

the condition of being unconformable.

Explanation:

Seen from Desert Tower, the Great Unconformity is the boundary between the flat-lying Tapeats sandstone (and overlying Paleozoic rocks) and tilted rocks of the Grand Canyon Supergroup (GCS).

thats all I know so i hope this helps

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.