Shannon wants to investigate how erosion happens along shorelines. She researches the topic and learns that events such as high winds and rough waves during a storm can cause sand to more quickly wash away from beaches. Shannon decides to investigate more by conducting systematic observations. Which plan would help Shannon investigate erosion using systematic observation? collecting shells from different beaches and arranging them in size order photographing and comparing the sand at beaches before and after storms creating a model shoreline, changing the wind speeds, and measuring changes in the sand using a hose with different amounts of force to spray sand and studying the differences