All the isotopes of a given atom have (1) the same mass number and the same atomic number (2) the same mass number but different atomic numbers (3) different mass numbers but the same atomic number (4) different mass numbers and different atomic numbers

In november 1987, a massive iceberg broke loose from the antartic ice mass and floated free in the ocean. the chunk of ice was estimated to be 98 mi long, 25 mi wide, and 750 ft thick. a typical backyard swimming pool contains about 24,000 gallons of water. how many of these pools could you fill from the water in this iceberg? (assume the iceberg is a rectangular solid of the above dimensions and consists of water only). express answer in scientific notation.