[Challenge] Time to learn how to jump, young grasshoppers

The Grasshoppers Challenge

This will be broken into 3 phases with increasing difficulty. This first challenge I want to make very easy so people can use it to progress onto other challenges so here it is:

Rocket Constraints: Any

Code Constraints: None

Phase 1: Launch a rocket and make it hover at exactly 100m.

Phase 2: Launch a rocket and make it hover for 15 seconds at 100m. Then perform a soft landing back on the ground.

Phase 3: Launch a rocket and make it reach and hover at 70Km. Then perform a soft landing as close to the launch pad as possible.

Phase X (The Secret Mission): Launch a rocket and land it on the VAB.

Good Luck!