Gravitation is a __(i)__ force unless __(ii)__ masses are involved. The force of gravity __(iii)__ with altitude. It also varies on the surface of earth, __(iv)__ from poles to equator.
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(i)------(ii)-------(iii)---------(iv)
Aweak---small --increases---decreases
Bstrong--large --decreases---decreases
Cstrong--small --decreases---increases
Dweak---large --increases----increases
correct answer is (a). How come force of gravity increases with altitude?