-Pencils were first used in 1662.
-Graphite is a crystalline form of the element carbon with its atoms arranged in a hexagonal structure.
- HB is a graphite hardness/grading scale: the higher the number next to H, the harder and lighter/less dark the pencil lead is.
- The H stands for “hard.”
Answer:
When non metals such as nitrogen and phosphorus are solids, they tend to be very dull and brittle which is due to the tendency of elements to revert to their original form.
By applying the containment strategy, the United States' objective was to prevent the expansion of the Soviet Union's influence in the world.
<h3 /><h3>What is the containment strategy?</h3>
It can be understood as a foreign policy strategy to prevent the spread of the communist system, being the policy that guided the Cold war, which took place between the USA and the USSR after the end of the second world war.
Therefore, the containment strategy is a foreign policy that aimed to influence the allies to prevent the strengthening of communism.
Find out more about Cold War here:
brainly.com/question/25774915
