I need help with this science/math question?

Question

mike finds an object floating in the lake. He can't tell if its made of cork or wood. He uses a balanceto find the mass to be 60.0milligrams. he drops the object into a graduated cylinder and watches as the volume changes from 7.0ml. what is the density of the object.

i fixed it

mike finds an object floating in the lake. he cant tell if it is made of cork or wood. He uses a balance to find the mass to be milligrams.he drops the object into a graduated cylinder and watches as the volume changes from 7.0ml to 7.25ml.
what is the density of the object. you need to convert nilligrams to grams first

i cannot figure this one out

Answer 1

density = mass x volume

Answer 2

density=mass/volume

mass=60mg
volume: I think there is something missing in the question, check your book again.