Why can water exists as Ice at zero degrees Celsius and also as a liquid at the same temperature?
Water freezes at zero degrees Celsius. At this temperature, a specific amount heat is lost to convert the liquid into solid (Ice). This amount of heat is known as the latent heat of fusion for water, and it does not affect the temperature of the water. At zero degrees, the water loses its latent heat of fusion to become Ice at zero degrees Celsius, hence no loss in temperature. Only a change in state is noticed during this change.
Does the divergence test confirm the convergence and/or divergence of a series?
The divergence can be used to prove that a series diverges (if terms of its sequence converges to any value other than zero), but this test cannot determine if a series converges. A series that converges must have the terms of its sequence converge to zero, but a series whose sequence converges to zero must not necessarily converge. One such example would be the harmonic series.
Why is C++ considered a static programming language?
Static programming languages require the programmer to specify what type of data would be stored in a variable. This is because the compiler needs as much information as possible during the compilation phase, unlike dynamic programming languages which binds the variable to its type at run time. As you might have noticed, C++ requires a type name before the variable name in the declaration of every variable, hence it is a static programming language.