If the mass of the slider increases does the coefficient of static friction also increase?explain​

No, it doesn't. Weight (sometimes) indirectly affects the frictional force but not the coefficient. The frictional force is proportional the normal reaction force which often (but not always) is equal to the weight. The constant of proportionality is the coefficient of friction or its reciprocal (depending on which side of the equation the constant is on). Situations when weight and normal reaction force are unequal when they are unequal. Normal reaction force is just a force to maintain the equilibrium of the body if it can.

Because the dept in the ocean