Yes. A mammal starts producing milk when her body realizes it's pregnant.
This will depend if she is at her peak of lactation, when the calf is drinking the most milk, therefore she is producing more. In this case she can be still producing milk for 3 or even 5 months after that. However, if the calf is nearing weaning age (about 10 months), than the cow might be producing milk for about 2 months. This will change from cow to cow depending on how well they produce milk, heavy milkers will produce longer than light milkers.
This is homework and Wiki won't help you cheat. Time to get to work and start thinking.
No. A cow (yes, a "female" cow--all cows are indeed females) must give birth to a calf annually in order to produce milk "at all times." Some cows can produce milk for two or more years if and only if they are milked regularly, but it is advisable to give them a break for two months or more before they start producing milk again.
Because she's a mammal, and when she gives birth to offspring she produces milk for that offspring to live off of for the next few months of its life.
Around the same length of time as a domestic cow: around 10 months.
They produce milk just like any other cow that is pregnant or not.
No
holstine
From when they are born to when they die
Apparently not. Although a cow does.
Provided this is a dairy cow you are referring to, and the calf has been taken away and fed milk replacer, the optimum length of time a cow can be "artificially stimulated" to produce milk is 10 months.
No. She is a dairy cow, one that is used to primarily produce milk.