The half-life of cobalt 60 is 5.3 years. What fraction of a sample remains after 21.2 years?

A.

one half

B.

one quarter

C.

one eighth

D.

one sixteenth

Is a tracheostomy permanent true or false?

The bare and rocky ground can only support what kinds of plants and animals?

During the lesson, you analyzed the DNA sequence of the housefly. For which of the following organisms would you expect the DNA sequence to be least similar to the houseflyÍs? 1. butterfly 2. grasshopper 3. monkey 4. beetle

In the winter, the air temperature suring the day might likely be

If a train was coming 104 mph and a car was coming 54 mph will the person in the car survive the crash?

Excess hydrogen ion is eliminated from the body largely by

Warming your hands by a fire is an example if which heat transfer? Give more examples of this type.

What is the name for a complex organized group of organisms?

Which of the following is NOT an argument used against genetically modified food? (A) It is new technology that unnaturally breaks genetic barriers between species (B) It might cause allergic reactions. (C) Humans should not be designers of life.

In multicellular organisms, cells are arranged into groups that work together to perform a common function. What are these groups called? bones joints systems tissues