I need help please on my physics hw

Assuming weightless pulleys and 100% efficiency, what is the minimum input force required to lift a 120 n weight using a single fixed pulley?

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?

Quantum mechanics applies to subatomic, atomic, nanometer-size, and micrometer-size systems. nanometer, micrometer, and kilometer-size systems. atomic, nanometer-size, and micrometer-size systems. subatomic, atomic, and nanometer-size systems.