The optic nerve needs a minimum of 2.00 x 10−17 J of energy to trigger a series of impulses that eventually reach the brain. How many photons of this wavelength, 6.8 LaTeX: \mu mμ m, are needed? Enter to 3 sig figs.

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.

true                                                                                                       true true true true true true

i think this picture will you.