Choose the correct statement for Periplaneta americana.

The exoskeleton of cockroaches and other insects is composed of which of the following?

What external changes are visible after the last moult of a cockroach nymph?

Which of the following statement$(s)$ is/are correct regarding cockroaches?
$(i)$ The body of the cockroach is segmented and divisible into three distinct regions - head,thorax and abdomen.
$(ii)$ Blood vascular system is of closed type.
$(iii)$ They are monoecious and both sexes have well developed reproductive organs.
$(iv)$ The development of $P. americana$ is paurometabolous,meaning there is development through nymphal stage.

In cockroaches,the outer margin of the tergum is bent downwards and is joined to the ........ in the cockroach.

What is the typical lifespan of a cockroach?