Answer:
a letter written by a person who is describing a current event
Explanation:
A primary source is a document from the time period of the event.
While most of these could be considered one, you have to do a process of elimination.
A scholarly article about an old event isn't a primary source, so it's not that.
An interview with a reporter who wrote about a current event is not a primary source because it is not the original document from the reporter.
A student's report about an event that occurred during her lifetime is a primary source, but it is not the best example.
Answer:
B. Petroleum
Explanation:
Silver is second.
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Traditional
In a traditional society the past is thought of as a best guide for the present. the traditional society stresses a great deal of importance into its patterned ways of doing things, and on its heroes and heroines and ultimitily is never readier to accept new knowlidge.
Troponin binds to Ca2+ from the sarcoplasmic reticulum. The propagation of an action potential along a skeletal muscle fiber causes the release of Ca2+.
What is a cross-bridge cycle?
As seen by the cross-bridge cycling, the action of the contractile proteins shortens muscles. The cross-bridge muscular contraction cycle can be seen in many types of muscles, including cardiac, smooth, and skeletal muscles. Therefore, when riding across bridges, all muscle groups contract.
What transpires in skeletal muscle during a cross bridge cycle?
The Pi dissociates after the myosin creates a cross-bridge with actin, causing the myosin to proceed through the power stroke and shorten the sarcomere, which lowers its energy state. In order to dismantle the cross-bridge
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