Answer:
A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. Physical properties include color, density, hardness, and melting and boiling points. ... To identify a chemical property, we look for a chemical change.
Answer:
1.Make an observation.
2.Ask a question.
3.Form a hypothesis, or testable explanation.
4.Make a prediction based on the hypothesis.
5.Test the prediction.
6.Iterate: use the results to make new hypotheses or predictions.
Explanation:
The combined mass of rock 1 and 2 = 19.28 + 25.3
= 44.58
Difference between rock 3 and combined rocks
= 46.3 - 44.58
= 1.72 grams
therefore, the third rock was 1.72 grams greater than the combined mass of the other two rocks.
Ecosystems need producers because they are the start of the food chain.
Producers are consumed by first consumers, the second consumers and so on.
<span>more prey than predators</span>