At the top of a hill, an athlete on a skateboard has X joules of mechanical energy. How much mechanical energy will she have at the bottom of the hill? Ignore the effects of friction. X joules less than X joules more than X joules There is not enough information to know.

the leaf is an organ of a typical plant, and the main functions are to complete photosynthesis and allow the plant to exchange gas, just like how we have the respiratory system. leaves have the stomata, which collects maintains co2 and o2 levels. this is necessary for cell metabolism. the leaf also collects sunlight using chloroplasts. succinctly, leaves own a pivotal role in sustaining plant life.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

answer///carbon;