Question: Some symbiotic relationships are obligate, meaning that both symbionts entirely depend on each other for survival. For example, many lichens consist of fungal and photosynthetic symbionts that cannot live on their own. Others are facultative (optional): they can, but do not have to live with the other organism.
Is there an answer to this question: What is the type of symbiotic relationship where the symbionts can live together but can also survive alone?

Answer: facultative

Question: The PermianTriassic extinction event, which was a prolonged event due to the accumulation of several extinction pulses, ended the dominance of the carnivores among the therapsids. In the early Triassic, all the medium to large land carnivore niches were taken over by archosaurs which, over an extended period of time (35 million years), came to include the crocodylomorphs, the pterosaurs, and the dinosaurs. By the Jurassic, the dinosaurs had come to dominate the large terrestrial herbivore niches as well.
Is there an answer to this question: During the Jurassic period which group came out as the most dominate for both carnivores and herbivores?

Answer: dinosaurs

Question: The standard specifies how speed ratings should be reported by the camera. If the noise-based speed (40:1) is higher than the saturation-based speed, the noise-based speed should be reported, rounded downwards to a standard value (e.g. 200, 250, 320, or 400). The rationale is that exposure according to the lower saturation-based speed would not result in a visibly better image. In addition, an exposure latitude can be specified, ranging from the saturation-based speed to the 10:1 noise-based speed. If the noise-based speed (40:1) is lower than the saturation-based speed, or undefined because of high noise, the saturation-based speed is specified, rounded upwards to a standard value, because using the noise-based speed would lead to overexposed images. The camera may also report the SOS-based speed (explicitly as being an SOS speed), rounded to the nearest standard speed rating.
Is there an answer to this question: What does the standard specify?

Answer: how speed ratings should be reported by the camera

Question: Classical statistical mechanics requires the existence of h (but does not define its value). Eventually, following upon Planck's discovery, it was recognized that physical action cannot take on an arbitrary value. Instead, it must be some multiple of a very small quantity, the "quantum of action", now called the Planck constant. Classical physics cannot explain this fact. In many cases, such as for monochromatic light or for atoms, this quantum of action also implies that only certain energy levels are allowed, and values in between are forbidden.
Is there an answer to this question: What is not required to exist in modern statistics mechanics?

Answer:
unanswerable