Why is the use of high-frequency radio waves a beneficial technological advancement for humans? Explain.
A. They have the best penetration.
B. They carry more information.
C. They travel over longer distances.
D. They do not require mediums to transmit.
I

I think It's C

Explanation:

due to higher waves can get easy transfers and receive those signals for most things, such as radios, TVs, phone signals etc etc

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.