23.2.5—Λ = 0.693 / t 1/2

use λ = 0.693 / t 1/2.

Use —λ = 0.693 / t 1/2 to connect the rule to the data and decision in the question.

This matters because —λ = 0.693 / t 1/2 determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —λ = 0.693 / t 1/2 to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Λ = 0.693 / t 1/2 is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.