Which In describing the motion of an object it is often helpful to identify a
allows you to describe its motion relative to that of another object.
O acceleration
O average velocity
O frame of reference
O speed

This is how zirconium appears in the periodic table. rounded to the nearest whole number, how many electrons are in an atom of zirconium?

Astudent creates a model of a closed ecosystem by filling a glass tank half full with water, then adding 10 snails and two small aquatic plants. the next day, all the snails are dead. what is the most likely cause of their death?

The necleus of an atom is made up of what subatomic particles?