Which of the following options are correct?

When a particle is placed on the surface of the earth, then the acceleration due to gravity is given by

…(i)

Now when the particle is at a height h form the surface then new acceleration becomes

…..(ii)

From eqn. (i) and (ii)

Therefore, acceleration due to gravity decreases with increasing altitude

Now, if a body of mass m is placed on the point whose angle of latitude is ϕ then acceleration due to gravity is given by

Where,

ω = angular velocity of earth

R = radius of earth

As the latitude increases, ϕ increases and cosϕ decreases, thus increasing the value of g

Therefore, (a) and (c) are correct option