2. Which fossil is the best index fossil? a. b. c. d.
3. Explain why you chose that fossil for number 2?
4. Based on the types of fossils above, in what type of environment/habitat were the rocks deposited in?

Will treating a viral infection with antibiotics affect the course of the infection? a) no; antibiotics work by inhibiting enzymes specific to bacteria. antibiotics have no effect on eukaryotic or virally encoded enzymes.b) no; antibiotics do not kill viruses because viruses do not have dna or rna.c) yes; antibiotics activate the immune system, and this decreases the severity of the infection. d) yes; antibiotics can prevent viral entry into the cell by binding to host-receptor proteins.