Key values of the following

Identify the animals using the following key

A non zero current passes through the galvanometer G shown in the circuit when the key K is closed and its value does not change when the key is opened. Then which of the following statement(s) is /are true?

Which one of the following is a key function of a firewall?

Name of the following: who proposed the lock and key theory?

Find direction of instantaneous induced current in secondary circuit for the following changes in primary circuit :- (a) Key is just closed (b) Some time after the closing of key (c) Key is just opened

Which one of the following box can be created by folding the given key design?