Look at the four devices below. flashlight
lawn mower
solar calculator
desk lamp
Which device uses light as it's source on energy?

Read this summary of a scientific theory: "cells are the most basic structural and functional units of life. all living organisms are made up of one or more cells. all cells that are alive in the world today came from pre-existing cells." which of the following would require this theory to be modified? -a.) a survey finds that a majority of people believe viruses carry out the basic processes of life. -b.) a prominent scientist says she feels strongly that one day the theory will be challenged by life on other planets. -c.) the dna of unicellular and multi-cellular organisms is shown to have many fundamental similarities. -d.) scientific observations show that microscopic organisms living in the deep ocean are not made up of cells.

What will happen to the amount of food available as a pondwater ecosystem ages

When wind creates a sand dune, the sheltered side of the dune is less steeply sloped than the windward side has the same incline as the windward side is more steeply sloped than the windward side