Which of the following best describes topsoil? a. topsoil is made entirely of decomposed organic remains. b. topsoil is made of humus and clay minerals washed down from the layer above the topsoil. c. topsoil is made of humus and mineral particles weathered from the soil's parent material. d. topsoil is made entirely of minerals weathered from the underlying parent material.

The answer is C.

Topsoil is made of humus and mineral particles weathered from the soil's parent material.

when the volume of gas is   changed from   717.73 ml   to 852 ml   the temperature will   change   from 315   c to 452   c

    calculation

this is calculated using the charles law formula

that is,   v1/t1 = v2/t2

          v1=?

        t1 = 315 c   into   kelvin = 315 +273 = 588 k

        v2 = 852   ml

        t2 = 425c + 273 =698 k

make v1   the subject of the formula ( by   multiplying both side by t1)

  v1=( v2 xt1) / t2

v1= (852 ml   x 588 k)/ 698 k= 717.73 ml