A current if 2.50amps flows for 20 seconds. How many moles of electrons flows at this time?

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

why is arctic sea ice important? arctic sea ice keeps the polar regions cool and moderate global climate. sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. as sea ice melts in the summer, it exposes the dark ocean surface.

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.