If the horizontal intensity due to the earth's magnetic field is 4 gauss at magnetic equator, then horizontal intensity of magnetic poles is _______. (Fill in the blanks.

If at a point on the surface of the earth, the horizontal component of the earth's magnetic field is 0.4 gauss and the dip angle is 60^@ , then magnetic field at that point in gauss is

Earth's magnetic field always has a horizontal component except at

Earth's magnetic field at a place has the horizontal itensity of 4 - units and total itensity of 5 units. The angle of dip is