Answer:
Black is the absence of all light. Things appear black when they do not reflect or emit light. White is the presence of all colors of visible light. Objects appear white when they reflect or emit all wavelengths of visible light (or at least three wavelengths - Red, Blue and Green - in equal intensity).
Explanation:
IPSec is the protocol that supports two encryption modes: transport and tunnel.
James Watson and Francis Crick discovered the double helix structure
Answer: It is a series of instructions contained in one command that users can apply to automate complex and/or repetitive tasks
One example would be a macro that goes through a list of numbers and highlights which are duplicates. Say you had the list {1,2,3,3,4,4,4,5}. You could use one color to highlight both 3 and 4 as they repeat themselves. Or you could use different colors to show the different values. With a small list, you could highlight by hand. However, macros are more efficient with larger lists.