Which of the following cannot be cured with existing drugs?
polio
smallpox
influenza
all of the above

All of the above.
They can be prevented, especially Polio.
Smallpox is common in children, but potentially deadly in baby's.
Influenza is the flu.

There are four nitrogenous bases that make up dna. the two pyramidines are thymine and cytosine. the two purines are adenine and guanine. these bases pair in a very specific way. adenine - thymineguanine - cytosine i remember it like this: a tall, good cat.