The correct answer is b.
The child is reaching for a toy which is not visible to him (hidden under a cloth), therefore, the child has a mental representation of the object in his/her mind. This action means that the child acknowledges that the objects continue to exist even when he/she can not hear or see them. This thought process is called object permanence and it is an ability acquired between the 4th and 7th month of a child's development.
They don't reproduce, as far as I know. They are produced in bone marrow.
Answer:
By changing the direction of your applied force
That would be the Sea Lampreys
A.Lampreys
Both seta and cheta or chaete means bristles. I think the term can be used interchangeably . Just check this link:- http://en.wikipedia.org/wiki/Polychaete It about polychaetes a class of annelid worms. These are extracts form the passage:- Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called *chaetae, which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms. Bundles of bristles, called *setae, project from the parapodia. http://en.wikipedia.org/wiki/File:Polychaeta_anatomy_en.svg Thats a cross section the terms have been used interchangebly.