Lemon juice has a ph of about 2.0, compared with a ph of about 1.0 for stomach acid. therefore, the concentration of h in stomach acid is than that of lemon juice.

the concentration of H in the stomach acid is greater than that of the lemon juice

Explanation:Please see attachment for explanation

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.