User: Many animals have body symmetry with distinct front and back ends. This type of symmetry is A. unilateral symmetry.
Cumulonimbus, from the Latin cumulus (heap) and nimbus (rainstorm, storm cloud), is a dense towering vertical cloud associated with thunderstorms and atmospheric instability, forming from water vapor carried by powerful upward air currents.
Panorama of a strong shelf cloud, a type of arcus cloud. Underside of a weak shelf cloud. An arcus cloud is a low, horizontal cloud formation, usually appearing as an accessory cloud to a cumulonimbus. Roll clouds and shelf clouds are the two main types of arcus.