Why did Sienna shift her position on the gymnasium
floor?
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.
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.

your answer would be a. 12.5 kg

most historians agree that gabriel mouton, the vicar of st. paul’s church in lyons, france, is the “founding father” of the metric system. he proposed a decimal system of measurement in 1670. mouton based it on the length of one minute of arc of a great circle of the earth (now called a nautical mile, 1852 meters). he also proposed the swing-length of a pendulum with a frequency of one beat per second as the unit of length (about 25 cm). a pendulum beating with this length would have been fairly easy to produce, thus facilitating the widespread distribution of uniform standards. over the years, his work was revised, improved, and extended by a number of french scientists.

the political sponsor of weights and measures reform in the french revolutionary national assembly was the bishop of autun, better known as talleyrand. under his auspices, the french academy appointed several committees to carry out the work of developing a usable system of weights and measures for france. one of the committees recommended a decimalized measurement system based upon a length equal to one ten-millionth of the length of a quadrant of the earth’s meridian (i.e., one ten-millionth of the distance between the equator and the north pole).