Five, use 300 grams of type A sulfuric acid with a concentration of $95 \%$ and 200 grams of type B sulfuric acid with a concentration of $70 \%$ to prepare type C sulfuric acid with a concentration of $\mathrm{m} \%$. How many grams of each should be taken to maximize the amount of type C sulfuric acid prepared?
Five, let the amount of type A be $x$ grams, and type B be $y$ grams, then $\frac{95}{100} x + \frac{70}{100} y = \frac{m}{100}(x+y)$. The result is: when $m=85$, type A takes 300 grams, type B takes 200 grams; when $85<m<95$, type A takes 300 grams, type B takes $\frac{95-m}{m-70} \times 300$ grams; when $70<m<85$, type A takes $\frac{m-70}{95-m} \times 200$ grams, type B takes 200 grams.