A$-$Transformer

Define the inrush current on transformers, explain the inrush current cause, effects, and how to reduce it$.$

read the nameplate of the following transformer and describe the following:

a$)$ Duty $($meaning and what types of duties can be found for transformers$)$

b$)$ Vector group $(($meaning and what types of vector groups can be found for transformers $)$

c$)$ Cooling $($meaning and what types of cooling can be found for transformers$)$

The rated frequency of the transformer below is $50Hz,$ if it is exported to the USA $/$ the frequency there is $60Hz,$ how the change of frequency will affect the rated value of the transformer?