Answer:
basically very cold areas
Radio waves are electromagnetic waves and as such travel at the speed of light. Waves emitted a century ago would be 100 hundred light years away. A light year is the distance light travels in one year. In one year light travels about 5.9 trillion miles. therefore the waves traveled about 590 trillion miles in a century.
RADIATION: Both conduction and convection require matter to transfer heat. ... Thermal radiation (often called infrared radiation) is a type electromagnetic radiation (or light). Radiation is a form of energy transport consisting of electromagnetic waves traveling at the speed of light.
doubling the radius will have a greater effect
v of cylinder=pi x square of radius x hieght
lets take an example,r=2,h=2
v=8pi
doubling the hieght,h=4
v=16pi ie twice the initial volume
doubling the radius,r=4
v=pi x 16 x 2
=32 pi ie four times the initial volume
therefore radius makes a bigger difference
