1. ............ is a large bag filled with hot air or gas to make it rise in the air, typically carrying a basket for passengers.

Balloon

Ballon

Baloon

Bollan

2. ............ is an airship or hot-air balloon, especially one that is tethered.

aurostat

aerustat

aerostet

aerostat

3. ............ are controlled by adding or reducing the heat, which adjusts the air density within it.

Cold-air balloons

Hot-air balloons

Hot-aer balloons

Hot-air balons

4. One of the ............ races he participated in produced a record-breaking trip from Japan to California.

hot air ballon

hot air baloon

hot air balloon

cold air balloon