What sample of matter is a single substance

Athin, square metal plate measures 14 cm on each side and has emissivity of 0.60. the plate is heated to a temperature of 745°c. what is the rate at which the plate radiates energy ? the stefan-boltzmann constant is 5.67 × 10-8 w/(m2 ? k4). remember that the plate will radiate energy from both its top and bottom surfaces.

Ascrew incorporates which other simple machine? lever wheel and axle inclined plane pulley

Positrons are spontaneously emitted from the nuclei of