Lethal Dose 50% (LD50) Practice Test

A chemical has $LD_{50}=70 \text{mg/kg}$. A $0.2 \text{kg}$ lab animal receives $7 \text{mg}$. The dose is $\frac{7}{0.2}=35 \text{mg/kg}$. Relative to the $LD_{50}$, this dose is:

A chemical has $LD_{50}=18\ \text{mg/kg}$. A test animal weighs $250\ \text{g}$. What is the $LD_{50}$ dose for this animal?