Could someone please explain isotopes, and what they do/are? If not thats fine, thank you

each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.

"some elements have only one stable isotope"

Explanation:

there ya go! Pls give me brainliest!

truck y has a greater velocity than truck x.

answer; how far out of place which the object finished relative to the starting location;