How do you get a false positive and false negative from classifier?

Means there was a test done and now it is understood that the test was wrong. i.e. a pregnant woman uses a pregnancy test and it shows up negative then sees her doctor and found out the test was a...

All the answers are false.

Yes. Both are quite possible.

False positive is a test result which indicates that a person has a disease or condition when, in reality, that condition/disease is not present.

different substances can react the same way when they're put into solutions. For example - if the substance in the known test was KCl and a precipitate was formed and in the unknown test a...