database normalisation

Question

consider:

T1: {A11, A12, A13} - key is A11
T2: {A21, A22, A11} - key is A21
T3: {A21, A23} - key is {A21 A23}

T1, T2, T3 all are in which normal form?

a) 2nf

b) 3nf

c) BCNF

FUNCTIONAL DEPENDENCIES ARE NOT MENTIONED. SO, PLEASE EXPLAIN HOW TO CHECK NORMAL FORM FOR THE RELATION?

Comments

@Red_devil

please tell how do you take/ assume the functional dependencies in a simple way with example?

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a key will always functionally determine the other attributes in its schema,actually its more difficult to construct the key from the list of FDs via closure.Here its straightforward.

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without giving FD's of relation it may be true A_{11}->A_{12}

A_{12}->A_{13}

A_{11}->A_{13}

it will be only in 2NF .is it possible or not???