BMAT Logic Question

I pay for 2 chocolate bars that cost £1.65 each with a £5 note. I receive 8 coins change, only 3 of which are the same.
Which TWO coins do I not receive in my change?

  1. 1p 2. 2p 3. 5p 4. 10p 5. 20p 6. £2 7. £1

Answer is E and F. I can’t solve this one. Please explain this to me