Select the four checks and balances set up by the constitution.
congress passes laws, but the president must sign them.
the courts can declare laws unconstitutional.
the president appoints, but congress approves, judges.
the president commands the military; congress declares war.
the states have certain powers not granted to the national government.
congress can impeach the president.

The correct answers are as followed:

1) Congress passes laws, but the president must sign them- This ensures that the legislative branch (Congress) does not have complete control over laws made by the federal government.

2) The president appoints, but Congress approves, judges.- This helps to limit the power of the presidency, as they must pick someone with credentials. Otherwise, that person may not be approved.

3) The president commands the military: Congress declares war- This makes it so that the decision to go to war is not decided by one person.

4) Congress can impeach the president- This procedure allows the Congress to chare a president with crimes they may have commited while they were president.

which statement explains one of the reasons world war 1 was so much more destructive than earlier conflicts