Que es un ambiente educativo y quien lo compone

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine

Ineed the answers for these promblems i have

The bar of prob. 5/82 is repeated here. the ends of the 0.4-m bar remain in contact with their re- spective support surfaces. end b has a velocity of 0.5 m/s and an acceleration of 0.3 m/s2 in the di- rections shown. determine the angular accelera- tion of the bar and the acceleration of end a.