| Answer | Crossword Clue |
|---|---|
| HALFLIFE | About 5700 years, for carbon-14 |
| PARSEC | About 3 1-4 light-years |
| Answer | Crossword Clue |
|---|---|
| HALFLIFE | About 5700 years, for carbon-14 |
| PARSEC | About 3 1-4 light-years |
Crossword
a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.