Which of the following are sentence fragments? I. Sarah who works at the CD store.
II. She smiled.
III. At noon tomorrow.
O I
A. I, II, and III
B. I and II
C. I and III
O D. II and III

600 dollars if i'm not mistaken.

a because they still enjoy the fire.

explanation:

the present continuous is a verb tense which is mainly used to indicates that an action is in progress at the moment of speaking.  

it is formed using: person + verb to be (am/is/are) +verb + - ing form  

example: i am studying at this moment .

in addition, the present continuous is also used in order to express things that will or will not happen in the near future.

example: i am having dinner with some friends tonight.

the speaker sometimes   uses it   to express that an action is repeated and it causes irritation on the part of the speaker

example: my sister is constantly complaining about everything.