The size of speaker represents which variable

Just took the quiz on edgenuity and the correct answer is "c.  4.54 x  10–12  j"

What are the activitys?   sorry if this took your points : (

Each calcium ion has a charge of +2, which can also be written as ca2+. if those ions move out of the neuron and no other ions are moving, the neuron would lose the positive charge associated with those ions and become more negatively charged.

Large asteroid and comet impacts. because they can have a huge impact on the environment, such as a loss of land, and crust on the earth with the big holes they produce. on the other hand, volcanic eruptions can also cause change within the environment by producing land, but im actually not quite sure which one would be a better answer, hopefully you read this and didnt just flat out choose the first sentence i have spoken! your welcome~