Grayson was doing his chores for his family. He was moving firewood from the truck bed to the woodpile. The distance between the truck bed and the woodpile is 43.7 meters. He hoped to finish his chores in half an hour because he wanted to go to the game with his friends. Grayson made seven round trips and finished after exactly 30 minutes. What was his average speed in meters per hours as he moved the firewood?

The hershey and chase experiments involved the preparation of two different types of radioactively labeled phage. which of the following best explains why two preparations were required? a. the bacteriophage used in the experiments was a t2 phage. b. it was necessary that each of the two phage components, dna and protein, be identifiable upon recovery at the end of the experiment. c. each scientist had his own method for labeling phage, so each conducted the same experiment using a different isotope. d. establishing the identity of the genetic material required observation of two phage generations.