Which of the following is the best thermal insulator?

a.) air
b.) water
c.) metal
d.) stone

i’m torn between a and b. i’ve asked many and people say a, but i asked my science teacher and she said b. and also i’ve researched and on answers. com also says water is the better insulator..but idk i’m conflicted! apex

According to the phase diagram for water, how is the state of water determined? proceed up a vertical line at any given temperature read the phase at the intersection of any given temperature and pressure at a given pressure, proceed horizontally to the s-l or l-g line

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m. the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

The pressure, volume, and temperature of a mole of an ideal gas are related by the equation pv = 8.31t, where p is measured in kilopascals, v in liters, and t in kelvins. use differentials to find the approximate change in the pressure if the volume increases from 14 l to 14.6 l and the temperature decreases from 375 k to 370 k. (round the answer to two decimal places.)