With the knowledge of bill of materials (Table 3) and labor hours (Table 4), the total cost for. manufacturing the steel vessel is calculated and summarized in Table 5. Given that the steel vessel. has a storage capacity of 564 kg of CGH2, its cost is $539 per kg of stored hydrogen.
Prehistoric (Archaeological) & Historic Periods. The Prehistoric Period consists of time periods in the origin and evolution of humankind from about 2.5 million years to about 900 BCE. the Prehistoric Period is divided into the Archaeological Periods of the Stone, Bronze and Iron Ages.
The period from the beginning of agriculture to the widespread use of bronze about 2300 bce is called the Neolithic Period (New Stone Age). Agriculture had developed at an earlier date in the Middle East, and the relationship of Europe to that area and the mechanism of the introduction of agriculture have been variously explained.