These are a kettle and an inkpot.
This is a kettle and (this is) an inkpot.
Which sentence is correct? Or both are correct? (The kettle and the inkpot are not considered as a single entity.)
Update. I've just come across some similar sentences in "Essential English" by C.E. Eckersley:
Is this a man and a boy? (accompanied by a picture of a man walking hand in hand with a boy) Is this a cat and a dog? (a picture of a dog, a cat and a bowl between them)
Why are two items considered as one and not separately?