In a high school graduating class of 100 students, 54 studied mathematics, 69 studied history, and 35 studied both mathematics and history. If one of these students is selected at random, find the probability that a.(2 pts) the student took mathematicsor history;b.(2 pts) the student did not take either of these subjects;c.(2 pts) the student took history but not mathematics.

Which of the following discoveries would be most likely to cause a scientific paradigm shift? a. the discovery of more rings around uranus b. the discovery of a new pathogenic virus transmitted by mosquitoes c. the discovery that a dormant volcano is showing signs of activity d. the discovery of a new species of salamander in the amazon rainforest e. the discovery that excess heat is radiating from the center of the earth and causing global climate change