Answer: Sediment Transport by Wind
Explanation: Like flowing water, wind picks up and transports particles. Wind carries particles of different sizes in the same ways that water carries them (Figure below). Tiny particles, such as clay and silt, move by suspension. They hang in the air, sometimes for days.
Answer : The molal freezing point depression constant of liquid X is, 
Explanation : Given,
Mass of urea (solute) = 5.90 g
Mass of liquid X (solvent) = 450 g = 0.450 kg
Molar mass of urea = 60 g/mole
Formula used :

where,
= change in freezing point
= freezing point of solution = 
= freezing point of liquid X = 
i = Van't Hoff factor = 1 (for non-electrolyte)
= Molal-freezing-point-depression constant = ?
m = molality
Now put all the given values in this formula, we get


Therefore, the molal freezing point depression constant of liquid X is, 
Answer: The answer to the first one is the second option and the answer for the second one is the first option.
Explanation:
B ia the correct one .
Hydrogen only uses the first energy shell, which holds 2 electrons, not 8.
Answer:
c. CH4 < NH3 because the NH bond is more polar than the CH bond.
Explanation:
Actually, the electronegativity difference between carbon and hydrogen is just about 0.4. This meager difference in electronegativity corresponds to a nonpolar bond between the two atoms.
However, the electronegativity difference between nitrogen and hydrogen is about 0.9. This larger electronegativity difference corresponds to the existence of a polar covalent bond between the two atoms.
Hence the N-H bond is significantly polar unlike the C-H bond. This implies that CH4 molecules are only held together by weak dispersion forces while NH3 molecules are held together by stronger dipole-dipole interactions and hydrogen bonds.