More stable substance that is produced by the decay of a radioactive substance is called?

the solar system used to have much dust particles option no d

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

thats how its supposed to be

the correct answer is:

a. formation of precipitation