What effect would the incomplete drying of a sample (for example, the incomplete removal of a re-crystallization solvent) on percent recovery?

It will lead to overestimation of the percent recovery

Explanation:

The percent recovery refers to the percentage of the pure compound recovered after a chemical process. It is a ratio of the pure compound recovered to the original substance multiplied by 100%.

If the sample was incompletely dried and the recrystallization solvent is still present, the percent recovery will be overestimated and we will have a value that is greater than the accurate percent recovery due to solvent impurities present.

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.