Disabled persons are the reason of slow production?

.No,lack of tools is. Give a disabled person the tool he needs he might produce better than any of us. So it's importent to keep researching and take disabled people into consideration while we are making tools. If there is no tools possible for a disabled one that means we lack of creartivity.

Every budy  is suted to accomplish a spacific task...  

Persons with disablity are part of our society. I don't think they slow the productivity. They perform their assigned task in best way without wasting time and resources in comparision to normal persons.

It simple physics. If we assume that God created all human equally fortunate (law of equilibrium) & all human have same number if skills but with variable level of accuracy (law of diversity), then a disabled person in one sense definitly means extraordinary abilities in another one (again, law if equilibrium)

First of all I do not call them Disabled People rather People with a Disability. No, they do not slow production. The problem is Companies (at least in SA) take them on for the scorecard and then they leave them there to their own devices with no actual training schedule or mentor. It's very much like people with no disability - take away their tools and they will slow production as they cannot perform. So Companies need to be progressive about actually upskilling these people and mentoring them.

it is depend on the type of work they do.

Don't think so. As employer has their own managerial system. And they would calculate the manhours and efficiency to customize the production timely.

Whether the person is disabled or not, as long as they can perform well on the given tasks, they are good contributors to the production. I strongly disagree with the opinion claiming that disabled are the reason for slow production. Disabled or people with special needs are more eager to play key roles in the development of their jobs and related productions. 

Depend on type of disability and type of work

Disabled has stronger ability in his other abled functions and it can be very usfel when he use it.

In the first, this question is very vague, and depends on your connotation. It seems that you want to put the horse in front of the cart!! I belive that a team member with one hand, one leg, one eye and one lung can provide more productive than another one who considered "completed charisma". Real disability lies in the heart & mind not in the body.

I have worked with disabled people and they are ABLE to perform tasks faster and better provided that those tasks are physically suitable to them.