Which of the following statement(s) is/are correct regarding excretory system of cockroach?

$(i)$ Excretion is performed by malphigian tubules.

$(ii)$ They absorb nitrogenous waste products and convert them into uric acid which is excreted out through hindgut.

$(iii)$ In addition, fat body, nephrocytes and urecose glands also help in excretion.

Which of the following statement(s) is/are correct about nervous system of cockroach ?

($i$) It consists of a series of fused segmentally arranged ganglia joined by paired longitudinal connectives on the ventral side.

($ii$) There are six ganglia lie in the thorax, and three in the abdomen.

($iii$) The sense organs are antennae, eyes, maxillary pulps, labial pulps and anal cerci etc.

($iv$) Each eye consists of about $5000$ hexagonal ommatidia.

The given figure shows open circulatory system of cockroach. Identify the structure that facilitate the flow of haemolymph by its contraction and relaxation

Which one of the following has an open circulatory system?

Which one of the following is not a characteristic feature of frog?

Explain : Cockroach is harmful for human beings.