Exercise 2 and 3

Exercise 2)
A rabbit jumps around at a field. The first jump is 1 meter, and afterwards the jumps are reduced with 5 percent. How high is the fifteenth jump?

Exercise 3 – PHYSICS)
In a bowl of freshwater weighs a piece of metal 30 grams. What is the volume of the piece of metal ?
The mass of the piece of metal is 81 grams, What is the density and what is the piece of metal made of ?