Answer:
1) Adenine (A) 2. Uracil (U) 4) Cytosine (C)
Explanation:
"RNA consists of four nitrogenous bases: adenine, cytosine, uracil, and guanine."
Answer:
The efficiency is 0.33, or 33%.
Explanation:
From the thermodynamics equations, we know that the formula for the efficiency of a heat engine is:

Where η is the efficiency of the engine, Q_1 is the heat energy taken from the hot source and Q_2 is the heat energy given to the cold object. So, plugging the given values in the formula, we obtain:

This means that the efficiency of the heat engine is 0.33, or 33% (The efficiency of an engine is dimensionless).
Answer:
All of these answers are dependent upon the specific scenario, but here are some general answers.
1. An object with a greater height will have more potential energy.
2. Potential energy can be changed into kinetic energy as an object falls. It loses height (potential energy) and gains speed (kinetic energy).
3. Depends on what scenario your class had.