Answer:
Option 2 and 4 are correct
Explanation:
The reactants in the attached image have more enthalpy and hence less stability as they are more reactive. Thus, Product is more stable than the reactants.
This is an addition reaction in which two reactants add up to form the product.
Very less activation energy is required as the reactants themselves are unstable, possess high energy and hence are very reactive.
Reactants have more energy than the products.
One-
The 6 is the only significant figure.
Answer:
The correct answer is option false.
Explanation:
Molality of the solution defined as moles of substance present in 1 kilogram of solvent.
Moles = 

Mass of percent (w/w%) of the solution is defined as amount of solute present in 100 grams of solution.

So, if want to inter-convert molality into mass percent we can do that without knowing density of solution.
Mass of solution = Mass of solute + Mass of solvent
The six steps of the scientific are:
1. State the question
2. Conduct research
3. Create a hypothesis
4. Perform the experiment
5. Analyze the data
6. Conclusion
So D. would be the correct answer, even though communicating the results could possibly be a step if it's required.