Create a variable X and assign to it the following matrix values:

X$=[((1$&$2$@$5$&$6)$&$(3$&$4$@$7$&$8)$@$(10$&$20$@$50$&$60)$&$(30$&$40$@$70$&$80))]$

Find the row and column indices of the matrix X whose values are greater than $20.$ Set all values greater than $20$ to the value $25.$ Set all elements of the second row equal to the value $17.$ Assign the value $2$ to each of the last three entries in the second column $($overwriting any changes you may have just made$).$