Q1. An alien DNA- like molecule is isolated from frozen remains of a life- form found beneath the Martian polar ice caps. In this example, for every base designated Q, there is twice that amount of base R; for every base Z, there is twice that amount of base S. If molecule contains 33.33 percent R, what percentage of Z would you expect?

Q2. Green olives may be preserved in brine, which is a 20 to 30 percent salt solution. How does this process prevent contamination by microorganisms?