Apaddler is approaching unfamiliar rapids. what should this paddler do? swim beside the paddlecraft to go over the rapids. aim for the middle of the rapids. go over the rapids as quickly as possible. go ashore well upstream to check out the rapids.

When a paddler is approaching unfamiliar rapids, he should go ashore well upstream to check out the rapids. When approaching rapids, go ashore well upstream and check them out before continuing. If you see dangerous conditions, carry your craft around them.

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).