Numbers behind the phenomena

Exercise and reference answers

Questions

1. Answer

   1752

   Question

   Year Franklin linked lightning to a spark

2. Answer

   7

   Question

   Richter magnitude above which quakes are destructive

3. Answer

   1000

   Question

   Times more energy for a rise of 2 in magnitude

4. Answer

   2001

   Question

   Year of the Bhuj earthquake

Instructions

Type the number only.

Explanation