Solve these clues to fill the grid.
- A soft heavy toxic malleable metallic element
- 1 Across
- A material made of cellulose pulp derived mainly from wood or rags or certain grasses
- 3 Across
- Serious disease where cells grow out of control
- 4 Across
- The 2nd letter of the Greek alphabet
- 8 Across
- The time required for something to fall to ___ its initial value
- 10 Across
- The vast area beyond Earth's atmosphere
- 13 Across
- The part of a scene that lies behind objects in the foreground
- 14 Across
- The smallest component of an element having the chemical properties of the element
- 16 Across
- The 1st letter of the Greek ___
- 2 Down
- Center of an atom or a cell
- 5 Down
- Hard piece of stone (plural)
- 6 Down
- A structure that has a roof and walls and stands more or less permanently in one place (plural)
- 7 Down
- An investigator who is employed to find missing persons or missing goods
- 9 Down
- The organic phenomenon of rotting
- 11 Down
- A unit of magnetic field strength equal to one-hundred-thousandth of an oersted
- 12 Down
- A piece of thin and flexible sheet metal
- 15 Down