ANSWER ASAP PLEASE why is there repulsion between the North Pole of these two magnets

A . The magnetic fields between the north poles repel each other

B . A new and different magnetic field forms between the two north poles

C . The magnetic fields between the South Poles repel each other

D. North poles repel each other , and south poles attract each other

10 newton object is placed 3 meters from the fulcrum. at what distance on the other side would you need to place a 15 newton object to balance the lever? show your work!

Atwo-stage air compressor operates at steady state, compression 10m^3/min of air from 100 kpa and 300k to 1200 kpa. an intercooler between the two stages cools the air to 300k at a constant pressure of 350 kpa. the compression processes are isentropic. a) calculate the power required to run the compressor, in kw b) compare the result to the power required for isentropic compression from the same inlet state to the same final pressure.

If the chemical properties of a substance remain unchanged and appearance or shape of a substance changes it is called a ?