Space

Solar system

100

The third planet from the Sun is called this. 

What is the Earth

200

This is the number of planets in the Solar System.

What is 9?

300

These 4 planets make up the terrestrial or inner planets

What are Mercury, Venus, Earth  and Mars?

400

Part a: This is the name of the galaxy containing our Solar system.

Part b: The galaxy containing our Solar System is this type of galaxy. 

What is the Milky Way

What is a Spiral Galaxy.