True or false?

The Watch Factory

In the factory, they suddenly realise that all the watches manufactured in September have faults in them.

Tick whether the statements below are true or false.

The manager takes a watch made in September and deduces
that it must have a fault.
true false

The manager takes a watch made in July and deduces
that it cannot have a fault.
true false
The manager takes a watch which has a fault and deduces
that it must have been made in September.
true false
The manager takes a watch which has no fault and deduces
that it couldn't have been made in September.
true false