Work Power Energy question bank (Physics)

The velocity at which $6$ kg mass (shown in figure) strikes the ground when it is released from a height of $6$ m above the ground is __________ m/s. Assume pulley is massless and string is light and inextensible. (Take g $= 10$ m/s$^2$)

A body of mass $1$ kg moves along a straight line with a velocity $v = 2x^2$. The work done by the body during displacement from $x = 0$ to $5$ m is __________ J.