1. explain how judicial review works as a check against congress. 2. what are some roles that the president plays in the u. s. government?3. what is the civil service and how do people join?4. what is the president's cabinet and what is their responsibility?

1. explain how judicial review works as a check against congress.

The judicial review checks if the law passed by the congress is constitutional. This limits the power of the congress - without it, it would have unlimited power, and could for example re-introduce slavery. The congress will not do it, because they know that the law would be deemed unconstitutional (due to 13th Amendment).

2. what are some roles that the president plays in the u.s. government?

The president is foremost a Chief of State - that also means the Head of State. This means that the president represents the US, for example during the meeting of the Heads of State. 

The president is also Chief Executive - the head of the executive branch of the government. This means that the president has the power to pass certain executive orders directly. 

3. what is the civil service and how do people join?
The US Civil Service is the workforce of people working for the Government in non-military positions. They are employed, and not elected, so they don't have terms. Those positions include administrative positions in the government. 

Nowadays, the Civil Service hires people like any other employer - though a selective process, where the applicants have to demonstrate their skills. 

4. what is the president's cabinet and what is their responsibility?

The Cabinet is the Council of the heads of the departments - it is the body that the President works with most directly, and it advises the president on their relevant areas of expertise. For example the Head of the Department of Agriculture would advice the president on the topics related to agriculture.