Firstly, I was just wondering if anyone could tell me what 8 binary levels are. The question is 'State the number of bits per sample needed to code for the 8 binary levels' I thought that this would just be 8 bits as that covers 256 choices, but I doubt it's that simple. Secondly, you have a normal car mirror, and then you extend it slightly with a flatter bit of mirror. Now obviously this will give you a wider vision, but would a disadvantage be that it distorts the view of the normal mirror? If you have two photos, the second photo is just a part of the first photo blown up without the amount of pixels changing, but the actual photo is the same size as the first photo. I presume that the resolution does not change as it is still the same image and same amount of pixels, just the pixels have increased in size? Finally, the last question.The rear surface of a car mirror can be heated electrically to clear frost and demist the mirror. A current I is passed through the reflecting alloy at the back of the mirror. The dimensions of the mirror are 0.20m length, height 0.08m. The heater dissipates 50W from the 12V car battery and the current is approx. 4A Calculate the thickness of the reflecting alloy film used to heat the mirror. Conductivity of reflecting alloy = 3.1 x 105S m-1 I actually haven't a clue how to approach this as when I tried, I got a ridiculous figure of 4.975 metres!