It means that the Romans became lazy and it also means having a harsh time or problems.
The correct answers are:
1. geothermal energy - It is energy produced from the heat of magma and other volcanic materials
2. lahar - It is an avalanche of water, mud, and other materials that a volcanic eruption can produce
3. tephra - It is volcanic rock and debris that is blasted from a volcano during an erruption.
The Monroe Doctrine was an effort to stop Europeans from influencing politics within the United States. (Lets say if Russia tried to turn the U.S communist during the cold war. The Monroe Doctrine would take into effect)
Isaac Newton promoted the idea that science must rely on repeated observation and experimentation.