According to IUPAC nomenclature, ethers are named as alkoxyalkanes where the larger alkyl group is chosen as the parent hydrocarbon. For compound (i), the larger group is the 4-carbon branched chain (isobutyl), making propane the parent with ethoxy at position 1 and methyl at position 2. For (ii), ethane is the parent chain with methoxy and chloro substituents; alphabetically 'chloro' comes before 'methoxy', so chloro gets position 1. For (iii), methoxybenzene (anisole) is the parent with nitro at para position (position 4). For (iv), propane is the parent with methoxy at position 1, matching the example in Table 7.2.