Lesson Objectives. 1  List the main features of the seafloor: mid-ocean ridges, deep sea trenches, and abyssal plains. 2  Describe what seafloor magnetism tells scientists about the seafloor. 3  Describe the process of seafloor spreading.
Assignment Help. The average diameter of sand dollars on a certain island is 4.50 centimeters with a standard deviation of 1.00 centimeters. If 9 sand dollars are chosen at random for a collection, find the probability that the average diameter of those sand dollars is more than 4.13 centimeters.he average diameter of sand dollars on a certain island is 4.50 centimeters with a standard deviation of 1.00 centimeters.
Round. Sand is defined by its size rather than what type of mineral it is. Particle size or grain size refers to the diameter of a grain of granular material. Technically, particles that fall between one-sixteenth of a millimeter to two millimeters in diameter are referred to as Sand.and is a common ingredient in many arena surfaces and ranges from very fine sand .075mm to very coarse 2.00 mm. Sand alone may be used but it is often combined with other particle sizes and other materials. Adding the proper depth of sand is a key factor. Too deep of sand can cause stress and injuries.