Aprime minister differs from a president in the following ways

The term president and prime minister can be used interchangeably,but their role differ in context to different countries. The president is the head of the state while the prime minister is head of the government. As head of government prime minister leads the operations of the government while a president is the chief representative of the county and performs ceremonial duties. He welcomes foreign dignitaries and acts as the commander in chief of the government. The method of their elections also vary, presidents are elected by the people while prime ministers are chosen by the party members.

whose power in the senate is equal to the power of the speaker of the house?

new evidence is discovered.

oversights and errors are corrected,

new technology is applied to evidence.