Build walls around the coast
Answer:
b. they can be observed and measured
Explanation:
Matter is anything that has weight and occupy space. There are three states of matter namely Solid, liquid and gas.
The properties of matter are both physical and chemical in nature. Both properties can be measured and observed. Phhysical properties are anything that can be measured without changing the state of the matter. Example of physical properties includes mass, volume, length, color etc.
Chemical properties is another properties of matter. This is the ability of the states of matters to combine with other substance to form a new product for example, rusting of iron, formation of salt etc.
All this as discussed are both measurable and can be observed.
If you will be rinsing your regulator after removing it from the cylinder, you must make sure that the dust cap is firmly in place.
<h3>What is Dust cap?</h3>
A dust cap is a gently curved dome mounted either in concave or convex orientation over the central hole of most loudspeaker diaphragms.
Thus, if you will be rinsing your regulator after removing it from the cylinder, you must make sure that the dust cap is firmly in place.
Learn more about dust cap here: brainly.com/question/10723016
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