What were president Theodore Roosevelt’s contributions?

What were president Theodore Roosevelt’s contributions?
【正确答案】：President Theodore Roosevelt’s contributions were as follows:
（1）The withdrawal of 200 million acres of public land as forest reserve and initiation of large-scale irrigation projects such as the Roosevelt Dam in Arizona at the expense of and under the supervision of the federal government.
（2） The active use of the Sherman Anti-Trust Act to stop monopolistic business mergers.
（3）The adoption of the Hepburn Act of 1906 to regulate railroad prices and do away with rebates （reductions）.
【题目解析】：
参见教材P208。