Which plant cell has no nucleus?

When coal has reached it hardest, darkest form, it is called select one: 0 a. sub-bituminous b. lignite c. bituminous d. antrhacite next page

During an experiment, readings for blood pressure in a persons body were found to be constant . however , when he measured by a different blood pressure cuff , the readings differed by 15 points for each reading. this difference indicates that the results are

Which characteristics are typical of a human population in the postindustrial stage?