What is the name of both the earth crust and the upper mantle collectively (both)?

lithosphere and asthenosphere

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.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.