There are none on the list you included with your question.
Answer:
answer a: a large front gear with a small back gear
answer b: a small front gear with a large back gear
Explanation:
just simple gearing ratios
Answer:

Explanation:
Mass of the helium gas filled inside the volume of balloon is given as




now total mass of balloon + helium inside balloon is given as


now we know that total weight of balloon + cargo = buoyancy force on the balloon
so we will have



