Water is a polar solvent. Since, 'Like dissolves like' a polar compound will be most soluble in water whereas a non-polar compound will be the least soluble.
The increasing order of polarity for the given organic compounds is:-
CH3OCH3 < CH3NH2 < CH3CHO < CH3CH2OH
Ether is the least polar and hence least soluble in water.
Answer:

Explanation:
Hello!
In this case, since the equation for the ideal gas is:

For each gas, given the total volume, temperature (28.1+273.15=301.25K) and moles, we can easily compute the partial pressure as shown below:

Best regards!