Symbols in text
As a general rule, avoid using mathematical or chemical symbols (Na, Ca2+, H2O, 14C, +, -, /, ÷, =, <, >, ∴, etc.) in the text. Very little space is saved. Not A rock (≈ 45 kg) fell into the water but A rock weighing about 45 kg fell into the water. Exception: symbols defining numbers ($, %, kg, etc.) are acceptable; ± is acceptable when joining numbers. Spell out units of measure when they are not accompanied by numbers. Several kilometres ...