Answer:
0.0979 N/c
Explanation:
Electric field, E is given as a product of resistivity and current density
E=jP where P is resistivity and j is current density
But the current density is given as
where I is current and A is area and 
Substituting this into the first equation then 
Given diameter of 0.259 cm= 0.00259 m and the radius will be half of it which is 0.001295 m

Answer: The temperature of the air affects the speed of sound in the due to the fact that colder contains air molecules with low kinetic energy. For warm air the kinetic energy of the molecules is high causing them to move in rapid motion. Because of these vibrations and collisions sound waves moves in a faster rate.
Explanation:
Answer: A) <u>Either source or listener must be moving.</u>
Explanation:
Frequencies can shift if an observer is moving relative to the wave’s source. This type of shift is called the Doppler effect (often used to analyze sounds). Think about the sound you hear when a police siren passes you and drives away; as the car increases its distance from you, the pitch of its sound becomes lower. This is because each wave is emitted from a greater distance, causing the wavelength to spread out or increase relative to you, the listener.
I believe it's b. A flashlight