Acelestial object takes six to seven years to revolve once around the sun. it’s made mostly of ice, some of which vaporizes when it passes near the sun. what is this object?

a) an asteriod
b) a comet
c) a meteorite
d) a planet

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 periodic table is arranged in order of atomic number."