What is a light-year?

question 14 options:

the amount of time it takes light to travel between 2 stars

the distance between 2 stars

the distance light travels in 1 year in a vacuum

Holes drilled several kilometers into earth’s crust provide direct evidence about earth’s interior in the form of

What equation is used to calculate the weight of an object on a plant ?

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.