D refers to denier which is a measure of the density of the fibers used in cloth. More specifically 1D means that 9km of the cloth fiber weighs 1 gram, 40D means that 9km of cloth fiber weighs 40grams.
The smaller the denier the more yards of fabric are produced per pound of cloth fiber resulting in thinner cloth with a finer weave. (small D = longer fiber per pound).
It can be a bit confusing. I hope that helps.
If you mean: 3d2+20d+12 then it is (3d+2)(d+6) when factored with the help of the quadratic equation formula
20d
Yes, you can. Any EF and EF-S lens will work on 20D.
no
You cannot record video/sound with Canon EOS 20D. It takes only photos with RAW/jpg output format.
4d (d + 5)
It is: 5d(4) = 20d
20ºC = 68.0ºF
A Canon EOS 20D can be purchased from any good camera store. If they do not have it in they can order it. If someone is happy to buy online then it can be bought on Amazon.
2(A+B)+20d-5d
A good place to buy the Canon EOS 20D is directly from Canon. Other good places to purchase this camera is from eBay or Amazon where one can often find discounted prices.
Canon replaced the 20D with the 30D that had more mexapixels and newer features. In fact, the 30D was replaced by the 40D, which was then replaced by the current (Jan. 2009) 50D camera body.