AQA A Level Biology Paper 2 Rat Question

Can anyone help me with the working out for this question:
Scientists investigated the production of laboratory rats with the characteristics of
type II diabetes. The scientists used the following method.
• They divided the rats into two groups, A and B, and fed them different diets for
2 weeks.
• They fed the rats in group A the normal diet containing 12% fat.
• They fed the rats in group B a high-fat diet containing 56% fat.
• After 2 weeks, they injected both groups of rats with 35 mg kg–1 of the drug
streptozotocin (STZ) to induce diabetes.
• 1 week later, the scientists determined the mean body mass and mean blood
glucose concentration for each group.
Calculate how many grams of STZ should be injected into a rat with a mass of 230.45 g. Show your working.
Give your answer in standard form.