Point a and point b are 50 meters apart. the temperature at point a is 60°c. at point b, it is 55°c. the temperature gradient between the points is . keeping other conditions constant, if the mantle and the crust were closer to each other, the temperature gradient between the two would be .

Motivation cannot be developed with practice; a person either possesses it or they do not.

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.

Which terms are used to identify pure substances