20. The Earth's core is made from iron and nickel and is divided into parts.
21. The Earth's inner core is made of
and outer core is made of.
22. The magnetic north pole in reality is the Earth'smagnetic pole.
23. The magnetic south pole in reality is the Earth'smagnetic pole.​

A17,250 kg rocket is pushed with a thrust of 6,450,284 n. what is the acceleration of the rocket?

Atank is filled with an ideal gas at 400 k and pressure of 1.00 atm . part a the tank is heated until the pressure of the gas in the tank doubles. what is the temperature of the gas?

An electron and a proton are held on an x axis, with the electron at x = + 1.000 m and the proton at x = - 1.000 m. part a how much work is required to bring an additional electron from infinity to the origin? express your answer with the appropriate units. part b if, instead of the second electron coming in from infinity, it is initially at x = + 20.00 m on the axis and is given an initial velocity of 100.0 m/s toward the origin, does it reach the origin? part c how close to the origin does it come?