Q144. Radioactive kcSr has a half-life of 30 years. What percent of a sample of kcSr will remain after 90 years? Physics — NUST Mock 2 — Question 144 of 200A. 0%B. 12.5%C. 50%D. 75%Practice more Physics MCQs for entrance exam preparation on Examora.io.← Previous Question Next Question →