The hardness of water is a measurement of how acidic it is.

select the best answer from the choices provided

t
f

Pluto was once classified as a planet. however, scientists no longer classify pluto as a planet. which is a likely reason for this change? the original hypothesis about pluto was supported. no observations of pluto were made in the past. several planets in outer space were found to be similar to pluto. there were significant changes in scientific knowledge about planets.