Only if you get the version with the built-in autofocus motor. The D3000 lacks a mechanical AF coupling so AF lenses which need to be driven by a motor in the camera body will require manual focussing.
Either way, you're far better manually focussing the Quantaray/Tamron 70-300mm: the AF performance is very slow, very noisy and hunts around a lot to achieve focus.
Although the Quantaray and Tamron versions are identical lenses, if you have to buy this low-quality budget model then go for the Tamron: it's absolutely no better lens quality (and usually the same price), but the manufacturer's warranty from Tamron is much better than Ritz and is internationally valid. If you resell the lens then the Tamron will have some value (not much though) and the Quantaray will be near worthless as it's not so widely known, and has a poor reputation amongst those familiar with the brand.
Answers & Comments
Only if you get the version with the built-in autofocus motor. The D3000 lacks a mechanical AF coupling so AF lenses which need to be driven by a motor in the camera body will require manual focussing.
Either way, you're far better manually focussing the Quantaray/Tamron 70-300mm: the AF performance is very slow, very noisy and hunts around a lot to achieve focus.
Although the Quantaray and Tamron versions are identical lenses, if you have to buy this low-quality budget model then go for the Tamron: it's absolutely no better lens quality (and usually the same price), but the manufacturer's warranty from Tamron is much better than Ritz and is internationally valid. If you resell the lens then the Tamron will have some value (not much though) and the Quantaray will be near worthless as it's not so widely known, and has a poor reputation amongst those familiar with the brand.
"Cheap" isn't always the same as "good value"...