My spouse worked for 5 hrs only in 2017, Do i need to file her tax return

HI,

I am full time employee working 40Hr/week, In 2016 I claimed my wife as dependent and filed taxes as Married-jointly.

In 2017, She worked for 5hrs later stopped working.

1) Can I still claim her a dependent? 

2) She did not receive any W2 from her employer s far , Do I need to file her tax returns also ?

3) Is there any minimum number of work hours required to get w2 or file tax returns

4) Also I received short term disability income in 2017, I did not see iton my w2, Do i need to report that also as income ?

Appreciate your inputs.