Because there is nothing to hear
I believe that Calpurnia finds the food on the back porch.
Answer:
An acid is a substance that donates hydrogen ions. ... Now there are more hydrogen ions than hydroxide ions in the solution. This kind of solution is acidic
Explanation:
A model is used to help scientists visualise things that they cannot actually see. It can be thought of as a thinking tool, to help form explanations. Models are useful simplifications to aid understanding. ... It can then be used to explain further phenomena and to make predictions of future behaviour.
Last option: Preserve an ecosystem
• The establishment of a bird reservation is a way to preserve an ecosystem because reservation provides suitable environment to organism. A healthy ecosystem means large number of biodiversity.
