In the past, developmental psychologists have not always done a significant amount of research on development beyond adolescence. today, they study the whole of the human life span. why do you suppose this change has occurred? in other words, why do they place a greater emphasis on studying how we change later in life, beyond childhood and adolescence?

Increased life expectancy lies at the heart of the matter

Explanation:

In the past, developmental psychologists have not always done a significant amount of research on development beyond adolescence. Today, they study the whole of the human life span.I suppose this change has occurred because as life expectancy increases adults continue to mature and develop in physical, cognitive, and social ways. Phycholgists place a place a greater emphasis on studying how we change later in life because more data from research will be necessary as the elderly population continues to grow.  

this statement is true.

forests are public goods, available for everybody. when usage of such a good becomes interesting for consumers and its usage increases, there can be a risk of overexploitation. it is a non rival good therefore, if one person consumes the good it does not reduce the availability for subsequent consumers.

these caracteristics require the establishment of measures in order to prevent the destruction of a commonly owned space, for example, to restrict the amount of people that have access to the same time.

c it has to be i googled it