We wish to test if a certain vaccine developed for a disease is effective or not. What is the best way to do this? a)Vaccinate 100 animals and expose all 100 to the disease. Vaccinate 100 animals and expose 50 of them to the disease.

b)Vaccinate 50animals, do not vaccinate 50 other animals, and expose all 100 to the disease.

c)Vaccinate 50 animals, do not vaccinate 50 other animals, and expose the disease

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

the food storage products of chrysophytes are oils or the polysaccharide laminarin.   formerly classified as plants, the chrysophytes contain the photosynthetic pigments chlorophyll a and c all but the yellow-green algae also contain the carotenoid pigment fucoxanthin.

the answer is 95 degrees