What was anton van leeuwenhoek's contribution in the development of cell theory? a. he built the first compound microscope. b. he was the first to observe live cells in a sample of pond water. c. he concluded that cells exist in liquids. d. he stated that all living things are made of cells. a. he built the first compound microscope. b. he was the first to observe live cells in a sample of pond water. c. he concluded that cells exist in liquids. d. he stated that all living things are made of cells.

answer: that would be cheating

explanation:

it's     c       this is a cell (b) with a nucleus (c) containing dna (a). the dna is organized into chromosomes (d). a section of the chromosome that codes for a trait is called a gene (e).

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.