Please help me i’m clueless and need assistance this is the question i need help with.

What would you expect population of sand dollars to be
if they sampled 8 m' of the reef? 12 m??

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.