Sam has been spending a lot of time at crew practice. which of the following statements shows how sam's girlfriend could be a negative influence?
"we never get to have fun anymore. do you really want to stay on the team? "

"make sure you don't overexert yourself. i've noticed you are really tired each day."
"did you remember to stretch? that might be why your arms hurt after the race."

"try to keep a moderate pace instead of pushing to win. your health is more important."

You isolate an infectious substance capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. you have four methods at your disposal to analyze the substance and determine the nature of the infectious agent.i. treat the substance with enzymes that destroy all nucleic acids and then determine whether the substance is still infectious.ii. microscope.iii. culture the substance on nutritive medium, away from any plant cells.iv. treat the sample with proteases that digest all proteins and then determining whether the substance is still infectious.if you already know that the infectious agent was either bacterial or viral, which method(s) listed above would allow you to distinguish between these two possibilities? a) ib) iic) ii or iiid) iv