Meredith wants to use a model to study how interesting formations such as arches, towers, and balanced rocks are made by erosion. she learns in science class that these can form when different layers of the rock erode at different rates. meredith decides to use running water to cause the erosion. to model the rock, she can choose from the following: potting soil clay pebbles plaster sand how should meredith make her model of the rock? a. by using each material to make a separate model b. by arranging the possible materials in strips, one next to the other c. by mixing all the materials together evenly d. by arranging the possible materials in layers, one on top of the other reset submit