Chemical: can burn
physical: hard
Answer:
The method of A. Limits requires this.
Explanation:
The method of limits is generally used in research and it is used to <em>establish an individual's perception of a certain stimulus</em> through understanding the level at which it is perceived by him/her.
The stimulus is <em>presented and varies</em>, by being <em>decreased or increased</em>, until it is perceivable by the individual. The experimenter needs to vary the perceptible stimulus until it is no longer perceived and the imperceptible stimulus until it is perceived in order to measure the level at which perception is possible.
Answer:
as america was being created it was "progressing" to be a country a better country
Explanation:
