Identify which type of machine learning would be most helpful in each scenario.

$\backslash$table$[[\backslash$table$[[$Terrance needs to train a$],[$system to identify patients$],[$whose symptoms indicate$],[$various common diagnoses.$]]],[\backslash$table$[[$Leo needs to train a system$],[$to identify unexpected$],[$relationships between$],[$customer demographics and$],[$the products that they$],[$purchase$.]]],[\backslash$table$[[$Malia needs to train a$],[$system to detect indications$],[$of fraud using both known$],[$and unknown techniques$],[$based on the limited dataset$],[$of known fraud techniques.$]]],[\backslash$table$[[$Evelyn needs to train a$],[$system to determine the$],[$best timing for a network of$],[$traffic light signals.$]]]]$

robot takes up$.$