Type the number

Exercise and reference answers

Questions

1. Answer

   300

   Question

   Million years ago coal forests were buried

2. Answer

   200

   Question

   Substances in coal tar, about

3. Answer

   1810

   Question

   Year London lit streets with coal gas

4. Answer

   1859

   Question

   Year of the world's first oil well

5. Answer

   1867

   Question

   Year oil was struck at Makum, Assam

6. Answer

   1820

   Question

   Year New York got coal gas lighting, around

Instructions

Type the number only.

Explanation