There are 6.02 × 1023 atoms in 1 gram of hydrogen. how many atoms are there in 400 grams of hydrogen? write your answer in scientific notation. if necessary, round your answer to two decimal places.

The radius of the base of a cylinder is 10 centimeters, and its height is 20 centimeters. a cone is used to fill the cylinder with water. the radius of the cone's base is 5 centimeters, and its height is 10 centimeters.

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry