Derailleur gears a detent or ratchet mechanism which stops the gear lever, and hence the cable and the derailleur, after moving a specific distance with each press or pull. Indexed shifters require re-calibration when cables stretch and parts get damaged or swapped. On racing bicycles, 10-gear rear cassettes appeared in 2000, and 11-gear cassettes appeared in 2009. Most current mountain bicycles have either. Many modern, high-end mountain bikes have begun using entirely one chain ring drivetrains, with the industry constantly pushing the number of rear cogs up and up, as shown by SRAM's Eagle groupsets (1 by 12) and Rotor's recent 1
Word sort understanding that can be developed in a variety of ways. Comparing sounds is the easiest task for developing phonemic awareness. Sound sorts can be introduced very early on and develop strategically throughout primary learning. An ability to sort sounds is essential for early reading because sound manipulation is a stepping stone to word study and decoding ability. For some students a direct instructional approach is not necessary in the development of sound study and sorting. Other children who have had less exposure or lack the understanding of sounds and their manipulability may need further instruction to develop their ability. Teachers