So for my chem class, i have to measure a notebook, a pencil, a regular house key, a calculator, and a pair of scissors i have to use a centimeter ruler that goes from 0-14 cm i have to use a centimeter ruler that goes from 0-140 cm i have to use a millimeter ruler that goes from 0-140 mm then i have to answer this question which ruler has the greatest precision? , i need the exact measurements

a force of 500                  

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.