Please help!! What allows negative feedback to control a system?
A. The system slows down when input is reduced.
B. The system has parts that sense the amount of input.
C. The system speeds up when output is increased.
D. The system has parts that sense the amount of output.

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples