For Iron:

For Oxygen:

These are the two chemical symbols for the two elements found in Iron Oxide.
Answer:
Thermometer A, because it measures accurately to the tenths digit.
Answer:
Alfred Wegener proposed the theory of continental drift – the idea that Earth's continents move. Despite publishing a large body of compelling fossil and rock evidence for his theory between 1912 and 1929, it was rejected by most other scientists.
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Unburned hydrocarbon on reacting with oxygen undergoes combustion reaction. However, the activation energy of this reaction is significantly high. When a catalyst like Pd is added to the reaction system, it provides active sites for the reaction to occur. It acts are a heterogeneous catalyst. It is pertinent of note that catalyst is refereed as heterogeneous, when it exist in different phase as compared to reactant and products. In present case, reactants and products are in gas phase, while catalyst is in solid phase. Due to availability of larger surface area at active site of Pd, activation energy of reaction decreases and decrease in activation energy favors higher reaction rates.
Answer:
C
Explanation:
This is essentially one of the several safety measures in the chemical laboratory. This particular approach is one used in the case of fire eventualities.
A is wrong
This is because in the advent of a fire incident, it is necessary to evacuate the building as a whole. Meeting in the hallway is still within the building which is not the right thing to do when there’s a fire outbreak. Occupants are expected to leave the building immediately
B. Is also wrong. Taking time to pack your belongings might make you be caught in the inferno. It is expected that you leave the building at once