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 Bronze Age began 5,500 years ago in the present-day areas of Turkey, Iran, and Iraq, which was also the cradle of human civilization. By this time, permanent settlements were already a few thousands years old, but it took time for these early people to discover the potential of metallic ores.