What is the historical context of the preamble

And intervening opportunity is an example of

After you make a decision, the next step in the decision-making process is to this step will you determine whether you made the right choice.

Which of the following activities would conserve the most energy? installing a dimmer switch on a light using a blender instead of a food processor hanging clothes to dry on a clothesline instead of ironing them opening a window instead of turning on the air conditioning setting your computer's screen saver to turn on after less time has elapsed