The child hears the bell (which rings continuously) of an ice cream wagon, goes out to the street and buys ice cream, bites the ice cream, and salivates. the sound of the bell will become a(n) going to the street to buy ice cream.

it's c. (to reduce the greenhouse effect/carbon gasses)

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

idk what the options are but

these is a strong electrostatic attraction between the ions hence a lot of energy is needed to overcome this attraction

this is why the boiling points are so high

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%