20 ml of alcohol combined with 90 ml of distilled water would yield what % v/v concentration

The answer for #3 is c but i don't know why

Agas diffuses 1/7 times faster than hydrogen gas (h2). what is the molar mass of the gas? 100.10 g/mol 98.78 g/mol 86.68 g/mol 79.98 g/mol

what is your question? collegechemistry 5+3 pts 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.