Which type of operating system allows multiple users to access and use the system simultaneously?

At least some singers are dancers. Some dancers are not lyricist.

Statements: 

Few Blue are Purple.

No White is Purple.

Some White is Black

Conclusions:

Statements: All milks are teas.

Some teas are coffees.

Conclusions I. Some teas are milks.

II. Some coffees are milks.

Statements:

Only a few player is team

Only a few team is sport

No sport is game

Conclusions:

Statements: Some bottles are not cans.

All boxes are drawers.

No can is a box.

Conclusions: I. Some boxes are not bottles.

Statements:Some mugs are soaps.

Some soaps are taps.

Conclusions:I. Some taps are mugs.

II. No mugs is tap. 

Conclusions:

I.No Charger is Socket.

II.Some Plug being Battery is a Possibility

Statement:

All diamonds are heart.

All hearts are Star.

Some hearts are Gold.

Conclusion:

Statement : Only a few White is Blue

Only a few Blue is Red

All Red is black

Conclusion

Statements:

All bags are polythenes.  

Some polythenes are points.    

Only a few points are jutes.