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A student wants to answer the question "Does adding calcium powder to soil make pea plants grow faster?" She adds calcium
powder to the soil of 12 plants and does not add it to the soil of a second group of 12 plants. She measures the growth of all of
the plants in each group for a month. Which statement best summarizes the factors that need to be controlled in this
experiment?
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The image shows a sandstone formation with visible bands of different colors. what do the bands indicate about how this sedimentary rock was formed? choose two answers. a). the rock was made from more than one material. b). water was absent during the compaction and cementation process. c). sediments and other matter were deposited in layers before lithification. d). the rock was stretched horizontally by the pressure from surrounding rocks. e). layers of hot liquid in the rocks cooled and solidified at different tempatures