Mark was upset because he only got half a sandwich while his older sister got two halves of a sandwich. After his mother cut his half sandwich into two pieces, Mark was perfectly happy. Mark is probably in the stage of cognitive development.

Preoperational

Explanation:The preoperational stage of cognitive development as described by Jean paoget marks the second stage of a child's cognitive development which occurs after the sensorimotor stage. The preoperational stahe usually manifests in children between the age of 2 and 7 years of age. The main highlight of this stage is the thinking ability of children who learn or base thir thinking on symbolic representation rather than logic or cognition. In the context above, Mark believes that getting two sandwiches is more than getting one, irrespective of the size and hence, the reason he felt cheated when he got one and was happy when that one sandwich was divided into two halves and handed over to him.

earlier philosophers whose work influenced the enlightenment included bacon, descartes, locke, and spinoza. the major figures of the enlightenment included beccaria, diderot, hume, kant, montesquieu, rousseau, adam smith, and voltaire. it spread the ideas of the enlightenment across europe and beyond.