A 40cm long tube has a 40 cm long insert that can be pulled in and out. A vibrating tuning fork is held next to the tube. As the insert is slowly pulled out, the sound from the tuning fork creates standing waves in the tube when the total length l is 42. 5cm, 56. 7cm, and 70. 9cm. What is the frequency of the tuning fork? (assume that the speed of sound is 343m/s).

Afarmer began a new method of reducing grain spills. this reduced the number of mice on the farm. the number of snakes in the surrounding area decreased at the same time. the snakes depended on the mice that lived in the field. what’s the likely reason the snake population decreased? a. the number of snake predators increased. b. the number of mice increased. c. the number of mice decreased. d. the pesticides affected the snakes. e. a new breed of mice moved into the field.