A \(20-\mathrm{kg}\) child running at \(1.4 \mathrm{~m} / \mathrm{s}\) jumps onto a playground merry-go-round that has inertia \(180 \mathrm{~kg}\) and radius \(1.6 \mathrm{~m}\). She is moving tangent to the platform when she jumps, and she lands right on the edge. What is the rotational speed of the merry-go-round and the child if the merry-go-round started from rest? Ignore any friction in the axle about which the platform rotates.