| Answer | Crossword Clue |
|---|---|
| RADIX | e, in natural logarithms |
| EULER | Mathematician who introduced the symbol e for the base of natural logarithms |
| FUEL | Natural gas, e.g. |
| DYERS | Non-natural blondes, e.g. |
| SOPRANOSAX | Its natural key is E flat |
| RESOURCE | Coal or natural gas, e.g. |
| EULER | He introduced the symbol "e" for natural logs |
| SCIENCE | It can be social or natural, e.g. |
