Can someone please answer these, I'm tired of wasting points on questions that no one answers. Describe the respective benefits of participatory design and contextual design, with examples of situations in which each might be preferred.

Outline which activities involve mathematical reasoning skills..

Explain the most appropriate methods to use in designing a product for the user in the following scenario, including aspects of the user interface that might need special attention.
Situation: A researcher approaches a designer with a request for a computer interface that will allow the evaluation of the ways children process spatial relationships and the various changes as they learn and develop. The computer interface will not have to perform any task but to play visual spatial games, recording and analyzing all elements in how children between the ages of 2 and 5 manipulate visual objects on a screen.