System documentation that includes the outcome of such structured diagramming techniques as data-flow and entity-relationship diagrams best defines: a. user documentation. b. application documentation. c. external documentation. d. internal documentation. e. embedded documentation.

C. external documentation.

Explanation:

External documentation :

External documents such as vouchers, invoices for payment, tax  VAT reports returns are produced because they are needed by someone from outside the company.  Within the company, internal documents are used to make decisions about different things.

Internal documentation as comments is written in a program.External documentation would include items such as flow charts, UML diagrams, documentation requirements, development reports, etc.

Therefore the answer is -

C

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day