Miriam read a book with an unknown number of pages. the first week, she read five less than 1/3 of the pages. the second week, she read 171 more pages and finished the book. write an equation that represents the total number of pages in the book.

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