What property of the gas helium makes it useful in balloons?

Helium has many unique properties: low boiling point, low density, low solubility, high thermal conductivity and inertness, so it is use for any application which can exploit these properties. Helium was the first gas used for filling balloons and dirigibles.

Helium is not used to make balloons, Its used to make them float. The answer is because it's such a dense gas.

hope that help

sand 60

clay 10

silt 30

sandy loam should be dominated by the sand. as the amount of sand increased, the amount of slit needed to anchor the plants' roots to the sand will also be increased. even though the amount is very little, 10% part of clay is still necessary for proper oxidation.

if your own plato the answer is b. the fern transitioned from sporophyte generation to gametophyte generation.