In humans, tongue rolling is dominant. Which of the following statements is true? a- You always know the genotype of a tongue roller.
b- You always know the genotype of a non-roller.
c- A tongue roller would always have a genotype of rr.
d- A non-roller has two possible genotypes.
HELP!!!

Which phrases describe an extrusive rock? check all that apply. fine texture cooled slowly small crystal size found deep underground different, easily observed minerals

3points hurry! what is the relationship between biotechnology, sharkskin, and disease resistance? bioengineers have developed an artificial sharkskin that does not allow resistant bacteria to grow on it. disease-causing microbes have been genetically modified to keep them from infecting the skins of sharks. scientists have created a device that can be attached to the skins of sharks that dramatically increases their abilities to resist disease. sharkskin produces many chemicals that can be collected and used to create antibiotics.

How much time has elapsed from the very beginning of "the memior of the conquistador bernal diaz del castillo" to the end? a. castillo's whole life b. a quarter of an hour c. a few weeks d. a decade