Two
Mollusks do not have antennae at all. Insects have antennae.
No, they do not have antennae.Insects have antennae. Arachnids are not insects, so they do not have antennae.
Insects with long antennae include beetles, grasshoppers, and moths.
No, not all insects have antennae. Some insect species have reduced or no antennae at all.
No, only insects have antennae. Clams are mollusks.
Mollusks do not have antennae at all. Insects have antennae.
They usually have a pair of antennae, though different insects have many different types. Source: wikipedia page on Insect_morphology#Antennae
Some insects, such as silverfish and bristletails, have antennae on both ends of their bodies.
Spiders are not insects and do not have antennae like insects. Outside of their fangs they have pedipalps which serve a similar function.
For seeing.
all insects have antenna
Antenna is singular - a car has a radio antenna. Antennae is plural - insects have two antennae.