Why is alternating current more effective at long–distance travel than direct current?
the power lines are made out of conductors.
transformers increase or decrease voltage as needed.
the ac generator is more efficient.
ac has lower voltage than dc.

If you are using PLATO, which I'm sure you are cause I've had the same question, the answer it the following:

Transformers increase and decrease voltage as needed.

radiation warms things up temp rises convection currents air circ windy weather

answer

procedural programming, object-oriented programming

explanation

procedural programming is a type of computer programming language that specifies a series of well structured steps and procedures   within its development period of time. it contains a systematic order of statements, functions and commands to complete a computational task or program. it is centered on creating procedures. while object oriented programming is a programming language that is centered on creating objects rather that actions and data rather than logic.. it has four principles which are inheritance, polymorphism, abstraction and encapsulation