How many spiracles are present in a cockroach (in $pairs$)?

In cockroaches,at the junction of $............$ and $............$,about $............$ yellow-colored,thin,thread-like Malpighian tubules are present.

Which of the following does not take part in excretion in a cockroach?

Match List-$I$ with List-$II$ related to the digestive system of a cockroach.

List-$I$	List-$II$
$A$. The structures used for storing of food	$I$. Gizzard
$B$. Ring of $6-8$ blind tubules at junction of foregut and midgut.	$II$. Gastric Caeca
$C$. Ring of $100-150$ yellow coloured thin filaments at junction of midgut and hindgut.	$III$. Malpighian tubules
$D$. The structures used for grinding the food.	$IV$. Crop

Choose the correct answer from the options given below:

Identify the location of hepatic or gastric caeca in a cockroach.

In female cockroach,the $7^{th}$,$8^{th}$,and $9^{th}$ sterna form a genital pouch. Which of the following pairs of sterna are primarily involved in forming the brood or genital pouch?