Gravitational Potential energy is given by the formula
[tex]U = mgH[/tex]
so it is product of weight of object and its height
for PE of cat weight is given as 300 N at height 6 m
[tex]U_1 = 300 \times 6 = 1800 J[/tex]
on other side we will have a bird of 50 N weight with height 50 m
[tex]U_2 = 50 \times 50 = 2500 J[/tex]
now here we can see that it depends on the product of weight and height both
so here PE of bird will be more than the PE of Cat