Which is a type of oxygen that forms a protective layer miles above the earth?

a.
fossil fuels

b.
smog

c.
pollution

d.
ozone

If you see someone who is injured at a workplace, the first thing you should do is a. call 9-1-1 or your local emergency number b. begin to administer first aid c. check the scene for danger d. try to discover what is wrong with the person select the best answer from the choices provided a b c d

Wich technque is not recommended for use as a supporting detail

Which of the following does not cause blindness? a. cataractsb. glaucomac. osteoarthritisd. diabetes