Question

is acceleration due to gravity remains same everywhere on earth? comment.

Answer 1

No due to the shape of the earth the force of gravity is maximum near the equator and least near poles

Answer 2

No. this is because, the shape of earth is not the same everywhere. The shape of the earth kind of like egg shaped, so the value of g is more at the poles than at the equator.
Also, the rotation of the Earth also influences the value of g. The value of g due to rotation (g₀) at a particular angle θ from the centre is given as:

g₀ = g - ω²Rcos²θ

where R is the radius of the Earth
g₀ is the new value for acceleration due to gravity 
g is the original value of acceleration due to gravity (taken as 9.8 m/s²)
ω is the angular velocity of the earth (in rad/hr.)