Sphere fits exactly in can -> means the radius of sphere = radius of the can.
let this radius be r, and diameter = 2r

Water just covers the sphere means the height of the water = height of the sphere = diameter

i) surface area of can in contact with water
= surf( base + curved surface)
= pi r^2 + 2 pi r (2r)

ii) Initial volume of water = Volume of cylinder(where h=2r) - volume of sphere = pi r^2 (2r) - 4/3 pi r^3
pi*r^2*(initial depth)= Initial volume of water solved above.
Solve for initial depth of water.