Answer:
<em>The correct option is theories. </em>
Explanation:
A scientific theory is a detailed explanation of natural researches which are supported through evidence. Scientific theories can be changed if other evidence are made which support another theory. Hence, scientific theories can change. The concepts of plate tectonics and evolution change overtime whenever new pieces of evidence are discovered. Hence, they are scientific theories.
Other options such as hypotheses are not correct because a hypothesis is just a tentative statement which can either be proved to be correct or wrong. Observations are not made on evidences hence the option observations is also not correct.
the major ethnic and language groups in the country
Answer:
In 2002, North Korea announced that it was changing to a free market economy ( last choice).
Explanation:
Indicators are substances that are used to test whether a substance is acidic or basic ot neutral in nature. They change their color when added to a solution containing an acidic or a basic substance. ... Naturally occurring indicators are turmeric, litmus, china rose and red cabbage.
