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 history of the region, and the development of the civilizations which flourished there, is most easily understood by dividing it into periods: Pre-Pottery Neolithic Age: Also known as The Stone Age (c. 10,000 BCE though evidence suggests human habitation much earlier).