To change from mass to weight is Fw = 30 kg * 9.8 m/s^2 = 294 N. To change from weight to mass divide by gravity (9.8 m/s^2).
Scientific Method: Because, they use their method which the scientific one to solve investigations.
Answer: Hydrogen Peroxide
Explanation: Hydrogen peroxide breaks down into oxygen and water. As a small amount of hydrogen peroxide generates a large volume of oxygen, the oxygen quickly pushes out of the container. The soapy water traps the oxygen, creating bubbles, and turns into foam.
Nuclear power
because thermal energy is obtained via the nuclear fuel.
Evaporation - Heating
Condensation - Cooling
Freezing - Cooling
Melting - Heating
Sublimation - Heating
Deposition - Cooling