Public health workers/leaders/advocates took a three ­pronged approach to increasing road safety targeting cars, roads and drivers through both technological advances and policies. as a result, the annual death rate due to automobile accidents has decreased by 90%.

a. true.
b. false.

During the first month of development, how many layers of cells make up the embryo? a. 1 b. 2 c. 3 d. 4

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

True or false. repeated drug use may lead to drug tolerance which occurs when a user requires larger amounts of the drug to achieve the desired effect.