which of the following can be distinguished using Lucas reagent??

1.methanol and ethanol

2.ethanol and Propan_2_ol

3.propan_2_ol and butan_2_ol

pl give reason for each case

Lucas reagent is used to distinguish between primary, secondary and tertiary alcohols. 
Hence the correct option is ethanol and propane-2-ol as ethanol is a primary amine and Propane-2-ol is secondary amine.
On the other hand, option 1 contains both primary alcohol and option 3 constrain both secondary alcohol which cannot be distinguish on the basis of Lucas test.