The medium ground finch lives on the Galapagos Islands. Birds with beaks of all sizes were originally part of this population. The finches are seed eaters. The types of food available for them to eat depends on the weather. During wet years, there is a large variety of food. During dry years, there is less food, and large, tough seeds are more abundant than small seeds. After a long drought, researchers noticed certain differences in the population of medium ground finches living compared to those who lived before the drought. What was different about the finches after the drought?

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н, о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.