Sienna is at soccer practice. She has just finished running two miles, and is very warm. The temperature outside is 95°F, and Sienna is beginning to feel overheated. Her coach takes her into the gymnasium and tells her to sit down on the floor and relax for a few minutes. Sienna notices that the floor feels cool against her skin. After a few minutes, however, the gymnasium floor no longer feels cool, and Sienna has to shift to a different part of the floor. Why did Sienna shift her position on the gymnasium floor?

Thermal energy was transferred from the gymnasium floor to her skin.
Her skin and the gymnasium floor reached thermal equilibrium.
Thermal energy was transferred from the air to her skin.
Her skin and the surrounding air reached thermal equilibrium.

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.

i wish i could but this one is weird give me abc and i can solve it.