ANSWER: Correct Chapter 1 Question 7 Â­ True/False Part A A scientific theory is a tentative or untested explanation that is proposed to explain scientific observations. This preview has intentionally blurred sections.
Gravel /ËÉ¡rÃ¦vÉl/ is a loose aggregation of rock fragments. Gravel is classified by particle size range and includes size classes from granule- to boulder-sized fragments. In the Udden-Wentworth scale gravel is categorized into granular gravel (2 to 4 mm or 0.079 to 0.157 in) and pebble gravel (4 to 64 mm or 0.2 to 2.5 in).
Soil particles come in three sizes: 1  Sands are the largest, and are coarse and gritty. 2  Silts are the middle-sized soil particles, and are smooth. 3  Clays are the smallest soil particles, and are fine and sticky. 4  An ideal soil would have equal amounts of sand, silt, and clay particles.