Dead leaves decaying, is it a chemical or physical change

Ill give brainiestif one neutron initiates a fission event that produces two neutrons in the products, how many new reactions can now be initiated? if each of the neutrons produced in the first fission event then initiates a fission event that produces one neutron in the products, how many new reactions can now be initiated by each neutron? how many neutrons in total were produced by the two fission events described?

Write balanced nuclear equations for the formation of five elements whose atomic number is between helium (2) and iron (26):

What is matter? a. anything that has mass and takes up space b. something that has volume and takes up space. c. things that have energy and take up space d. things that take up space but don't have mass