Mariner 4 and 9 and Viking 1 and 2 probes needed enhanced cameras and wireless communication equipment to take images of Mars's surface and send them back to Earth. According to the video, how did improving our technology lead to new discoveries about Mars?

According to the article, what valid claim came from the national research council? there is no association between fluoride exposure and increased cancer risk in humans. there is a possible link between fluoride exposure and increased cancer risk in humans. there is a definite link between fluoride exposure and increased cancer risk in humans.