Which of the following is an example of a niche? a. A squirrel living in a tree. b. A fish in a pond. c. A lion hunting for zebra in a grassland. d. Two birds flying in the air. Please select the best answer from the choices provided A B C D

In the circuit, the switch s has been open for a long time and r = 125 kohm. it is then suddenly closed. (a) determine the time constant before the switch is closed. s (b) determine the time constant after the switch is closed. _ s (c) let the switch be closed at t = 0. find the current in the switch as a function of time. (use t for time. express your answer in milliamps and seconds.) i(t) =_