The circumference of a 8in circle

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The weight of a radioactive isotope was 96 grams at the start of an experiment. after one hour, the weight of the isotope was half of its initial weight. after two hours, the weight of the isotope was half of its weight the previous hour. if this pattern continues, which of the following graphs represents the weight of the radioactive isotope over time? a. graph w b. graph x c. graph y d. graph z

Peter measures the angles in a triangle. he finds that the angles are 95, 10 and 75. is he correct? explain your answer