How many of the following cannot be differentiated by haloform test 

 

 

 

ii) 2- Butanol and 2-Butanone
iii) 2-Pentanone and 3- Pentanone
iv) 2-Pentanol and diethyl ether
v)  $PhCHO$ and  $PhCOPh$ 
vi) 1- Phenyl ethanone and 1-phenyl propanone
vii) Isobutyl alcohol and secondary butyl alcohol
viii) Acetone and acetaldehyde