The inhibitor is administered to infected hamsters at a daily dose of $75{mg\; kg}^{-1}$. Calculate the mass of this inhibitor, in $mg$, that should be administered daily to a hamster weighing $36g$. Show your working.

In a clinical trial, the concentration of bacteria in the blood of infected hamsters was measured after 4 days of treatment.

• In Group A (treated with a standard clinical antibiotic), the mean ${\log }_{10}$ number of bacteria per $mL$ of blood was $3.80$.
• In Group B (treated with the new ribosome inhibitor), the mean ${\log }_{10}$ number of bacteria per $mL$ of blood was $1.60$.

Calculate the percentage reduction in the actual bacterial concentration per $mL$ in Group B compared with Group A. Give your answer to 3 significant figures and show your working.

Explain why this ribosome inhibitor, which targets bacterial translation, is safe to use in humans and does not inhibit protein synthesis in human host cells.