Using the following information, find the final registers for x$6$ and x$7.$ With explantion if possible.

x$3=7$

x$4=8$

x$5=9$

x$6=10$

x$7=11$

addi x$3,$ x$4,6$

add x$5,$ x$3,$ x$4$

addi x$4,$ x$3,15$

add x$6,$ x$3,$ x$5$

addi x$7,$ x$5,12$