Answer:
E) A, B, and C
Explanation:
Syn addition refers to the addition of two substituents on the same face or side of a double bond. This differed from anti addition which a occurs across opposite face of the double bond.
Hydrogenation, hydroboration and dihydroxylation all involve syn addition to the double bond, hence the answer chosen above.
Answer:

Explanation:
Given,
The density of Helium is 
We need to find the density in Dg/μm
We know that,
1 g = 10 dg
1 cm³ = 10¹² μm³
So,

So, the density of Helium is equal to
.
Answer would be c hope this helped
Explanation:
The experiment is performed at a constant atmospheric pressure. The experiment proceeds by placing an empty flask in a boiling water bath. As the temperature increases, the air inside the flask expands. Afterwards, the gas is cooled in a water bath by maintaining the amount of the air in the flask constant.