Questions about HP 953xl

Can I use HP 953 M ink cartridges combined with HP 953 XL cartridges at the same time in my HP InkJet Pro 7730 printer?

HP 953: How do I recognise an already used cartridge ? Thank you very much i.V. [ernestb@web.de]

I have been unable to find the cartridges I need for my printer, but I have been unable to find the cartridges I need for my printer. How long do you guarantee the HP 953 cartridges you have in stock (on the back of the packaging)?

hello what is the difference between art. no. 13792781 and 14044643? to me they both seem identical. except for the price.

Hello, what is the difference between this product for 116.- and the HP 950XL/951XL (Y, M, C, BK, ink) for 109.-? I only see that this product prints 3x as many pages as the cartridges for 109.-. What is meant by Ink 4-Pack blister? Thank you very much for an answer.

Do these cartridges each have their own print head?

7720

Hoi, what is the difference between this product and this one: https://www.digitec.ch/de/s1/product/hp-953xl-multipack-y-m-c-bk-tinte-tinte-9414926 The product picture is exactly the same, but in the description this product can print more than three times as many pages with less capacity. How is that possible? Why does this one cost 40 francs more? In addition, I have seen that this one works for the 6950 and 6970 printers and the cartridge from the link works for completely different printers. How is this possible with the same product name? Thank you for your answer