Which is a pure substance?

A rock with a vein of gold.

A faceted diamond.

A glass of iced tea.

Bread dough on a wooden board with a rolling pin.
ITS A DIMOND

The wave shown on the electromagnetic spectrum disturb the medium it passes through a)different frequency. b)the same frequency .

Which of the following signs of a chemical reaction are observed in the reaction of potassium with water? precipitate formed temperature change smell produced gas produced color change

56.16 gregor mendel was the first scientist to use statistics to analyze scientific data. before mendel's experiments, scientists believed that organisms acquired traits from their environment and passed them on to their offspring. after mendel's discoveries were accepted, scientists realized that traits passed to offspring were the result of genes being passed from parents to offspring. this is an example of pls