The driving belt is twisted so that pulley $B$ rotates in the opposite direction

to that of drive wheel $A.$

If the angular displacement of $A$ is ${}_A=(5t^3+10t^2)rad,$ where $t$ is in seconds, determine the angular velocity of $B$ when $t=2s.$

Express your answer to three significant figures and include the appropriate units.

${}_B=$

Units

If the angular displacement of $A$ is ${}_A=(5t^3+10t^2)rad,$ where $t$ is in seconds, determine the angular acceleration of $B$ when $t=2s.$

Express your answer to three significant figures and include the appropriate units.

${}_B=$