Two 53 {\rm g} blocks are held 30 {\rm cm} above a table. As shown in the figure, one of them is just touching a 30-long spring. The blocks are...

Two 53 {rm g} blocks are held 30 {rm cm} above a table. As shown in the figure, one of them is just touching a 30-long spring. The blocks are released at the same time. The block on the left hits the table at exactly the same instant as the block on the right first comes to an instantaneous rest. what is the k constant?