In the following question, some part of the sentence may have errors. Find out which part of the sentence has an error and select the appropriate option. If a sentence is free from error, select 'No Error'.
Modern medicines has scored significant victories (1)/ against both infection and trauma - (2)/ the major causes of ill health and death. (3)/ No error (4)
Among four bags, average weight of last three bags is 18 kg and the average weight of first three bags is 19 kg. If the weight of last bag is 22 kg, then what is the weight (in kg) of first bag?