Which is a reason to use digital signals instead of analog signals to transmit information?
A. Noise decreases the loudness of analog signals but does not
affect the loudness of digital signals.
B. The waves used to transmit analog signals are more dangerous
than the waves used to transmit digital signals.
C. Noise changes the quality of analog signals but does not affect
the reliability of digital signals.
D. The waves used to transmit analog signals require more energy
than the waves used to transmit digital signals.

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

Atruck driver is attempting to deliver some furniture. first, he travels 8 km east, and then he turns around and travels 3 km west. finally, he turns again and travels 13 km to his destination. what is the drivers distance

Certain bacteria (such as aquaspirillum magnetotacticum) tend to swim toward the earth’s geographic north pole because they contain tiny particles, called magnetosomes, that are sensitive to a magnetic field. if a transmission line carrying 100 a is laid underwater, at what range of distances would the magnetic field from this line be great enough to interfere with the migration of these bacteria? (assume that a field less than 5% of the earth’s field would have little effect on the bacteria. take the earth’s field to be 5.0 * 10-5 t, and ignore the effects of the seawater.)