Please help me on my test :) thank uu An insulated copper wire is wrapped around an iron nail and connected to a power
source (battery). When the circuit is closed, the nail can attract and pick up paper clips,
but when the circuit is open, the nail does not attract the paper clips. Which of the
following explanations best describes this phenomenon?

A When the circuit is open, it creates a current, and a magnetic field is induced.
B When the circuit is closed, there is neither a current nor a magnetic field.
C When the circuit is closed, it creates a current, and a magnetic field is induced.
D When the circuit is open, there is a current but no magnetic field.

Utah's great salt lake has an average salinity seven times higher than that of the oceans. very few multicellular organisms live in this harsh environment. an example is the brine shrimp, which must devote a large portion of its metabolic energy to osmoregulation. these brine shrimp must available hint(s)utah's great salt lake has an average salinity seven times higher than that of the oceans. very few multicellular organisms live in this harsh environment. an example is the brine shrimp, which must devote a large portion of its metabolic energy to osmoregulation. these brine shrimp must pump water back into their cells to counter its loss due to osmosisactively pump water back out of their cells to counter its inflow due to osmosissynthesize membranes that are impermeable to substances that upset osmotic balanceactively pump salt back out of their cells to counter its inflow due to osmosis