The Reagan Doctrine

a. Allied the United States with Europe and Latin America against the Soviet Union
b. Asserted American interests in countries where the Soviet Union had been active
c. Sponsored cooperation between the Soviet Union and United States
d. Pursued a strict policy of nuclear deterrence

b. Asserted American interests in countries where the Soviet Union had been active

Explanation:

United states followed this doctrine from early 1980s until the end of cold war in 1991.

Under this doctrine , united states extended direct or indirect support to all anti communist movement in countries spread over Asia , Africa and Latin america . It was aimed at overwhelming the cold war in order to bring peace in the world.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.