I believe it is the very first one
hope it helps :)
Answer:
NaF and KBr
Explanation:
These two substances contain pure ionic bonds. LiI is a covalent compound because of the Large polarizing power of Li and the high polarizability of I(Fajan's rules). The other compounds mentioned are organic compounds. They are not soluble in water at all.
The solute is the part of the solution that dissolves in the second component (usually a fluid). Therefore, for the mentioned solution, the solute is ehyl alcohol since it is the one dissolving in water.
As for the solvent, it is the component in which the solute dissolves. In this case, it is water.
Explanation:
It is given that, the Average Speed of the orbiting space shuttle is 17500 miles/hour.
We need to convert the speed in kilometers/
second
We know that,
1 mile = 1.609 km
or
1 km = 0.621 miles
1 hour = 3600 seconds

Now cancel the miles in numerator.

So, 17500 miles/hour is equal to 7.82 km/s.