Consider the following two relations, named Customer and Person, in a

database:

Person (

aadhaar CHAR(12) PRIMARY KEY, name VARCHAR(32));

Customer (

name VARCHAR(32), email VARCHAR(32) PRIMARY KEY, phone CHAR(10), aadhaar CHAR(12), FOREIGN KEY (aadhaar) REFERENCES Person(aadhaar)); Which of the following statements is/are correct?

Consider a database relation $R$ with attributes ABCDEFG , and having the following functional dependencies:

$$ \mathrm{A} \rightarrow \mathrm{BCEF} \quad \mathrm{E} \rightarrow \mathrm{DG} \quad \mathrm{BC} \rightarrow \mathrm{~A} $$

Which of the following statements is/are correct?

Consider the following tables, Loan and Borrower, of a bank.

Query: $\quad \pi_{\text {branch_name, customer_name }}$ (Loan $\triangleright \triangleleft$

Borrower) $\div \pi_{\text {branch_name }}$ (Loan)

where $\triangleright \triangleleft$ denotes natural join.

The number of tuples returned by the above relational algebra query is

__________

Suppose $X$ and $Y$ are random variables. The conditional expectation of $X$ given $Y$ is denoted by $E[X \mid Y]$. Then $E[E[X \mid Y]]$ equals