Use the method of elimination to find the solution of the following pair of linear equations: $2x + y = 4$ and $x + 3y = 7$.

$A$ shopkeeper sells a saree at $8 \%$ profit and a sweater at $10 \%$ discount,thereby,getting a sum of $Rs. 1008$. If she had sold the saree at $10 \%$ profit and the sweater at $8 \%$ discount,she would have got $Rs. 1028$. Find the cost price of the saree and the list price (price before discount) of the sweater (in $Rs.$).

Solve the following pair of linear equations by the method of elimination:
$4x - 3y = 8$
$6x - y = \frac{29}{3}$

The present age of Ramesh is $x$ years. Mahesh is $5$ years elder than Ramesh and three years younger than Suresh. The present age of Suresh is $\ldots \ldots \ldots \ldots$

The graph of the equation $\ldots \ldots \ldots \ldots$ is parallel to the $Y$-axis.

Comparing the equation $x=4$ with the standard form $ax+by+c=0$,we get $b=\ldots \ldots \ldots$