Administration: Individual. The DAB-4 is a revision of one of the most popular individual achievement tests available. Its 8 subtests identify studentsâ strengths and weaknesses across important areas of school achievement. A supplemental manual shows how to probe student responses to obtain information about studentsâ thinking processes and problem-solving strategies.
In 1992, the first evidence of a planetary system other than our own was discovered, orbiting the pulsar PSR B1257+12. Three years later, 51 Pegasi b, the first extrasolar planet around a Sunlike star, was discovered.
Scientist used to say there were nine planets in our solar system. Pluto was discovered, scientists identified Pluto as the ninth planet in our solar system. In 2006 Pluto was demoted from the status of a planet to a dwarf planet.