Why does my machine's LCD show "NO CARTRIDGE" even though I have already installed new ink cartridges?

Is there a way to view how much ink is remaining?

I replaced my ink cartridge, but the LCD is still displaying "Ink Empty".  What can I do?

When selecting grayscale printing in the printer driver, does this use only the black ink or all the ink cartridges to produce the grayscale image?

Why can't I print when an ink cartridge is empty?

Why do the color ink cartridges run out of ink even though I never or rarely print in color?

How do I replace the Ink Cartridge?

Can I print using only the black ink cartridge when the Color cartridges have run out?

Is there any way to reduce Ink consumption?