Which of the following lists the composition of the earth’s outer core?
a. calcium, potassium
b. silicon, aluminum, calcium, sodium and potassium
c. iron, nickel
d. oxygen, magnesium, iron, aluminum, and calcium

The volume of a gas is halved during an adiabatic compression that increases the pressure by a factor of 2.5. what is the specific heat ratio? show the math steps .

Ways that industry and agriculture use physical properties to separate substances

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.