The image above show four Nutrient Agar plates each inoculat…

The image above show four Nutrient Agar plates each inoculated with a bacteriophage called COVID-20, and with bacterias A, B, C, and D respectively. After 24 hours of incubation contrast light was used to better observe the plaques as clear white dots. According to the results, what is the host range of the unknown bacteriophage?

An unknown sample has been given to you and you must enumera…

An unknown sample has been given to you and you must enumerate the phage load. You begin your investigation by serially diluting a sample resulting in the following dilutions: 10-2, 10-4, and 10-6. You spread 100 µL of 10-2 and 10-6 dilution onto a separate nutrient agar plate and incubate for 48 hours. Upon examining your plates, you observe the following results:  10-2: 100 PFU,  Calculate the phage titer for the plate in PFU/mL.