Today's radio consists of an antenna, printed circuit board, resistors, capacitors, coils and transformers, transistors, integrated circuits, and a speaker. All of these parts are housed in a plastic case. An internal antenna consists of small-diameter insulated copper wire wound around a ferrite core.
Answer:

Explanation:
Soil bearing pressure=
Since we're given pressure of 2500 psf and load of 45000 pounds
The area=
Therefore, the smallest area of safe footings should not be less than 
Answer:
#See solution for details.
Explanation:
#The commutative property of multiplication tells us that it doesn't matter in what order you multiply numbers. The formula for this property is a * b = b * a:

Hence, the product of the four numbers remains 320,000 irrespective of their order.
Because of the skin depth effect, the current at high frequency tends to flow at very low depth from radius. Then at high frequency the effective cross section of the wire is narrower than at DC.
Fro example skin depth at 100 kHz is 0.206 mm (0.008”), a wire more thicker than AWG26 could be a waste of copper, better use a bunch of thin wire (Litz wire) to rise the Q factor.
Answer:
Pressure = 11.38 psi
Force = 13.981 Ibf
Explanation:
Step by step solution is in the attached document.