Consider the figure below, where a TCP sender sends $8$ TCP segments at t $=1,2,3,4,5,6,7,8.$ Suppose the initial value of the sequence number is $0$ and every segment sent to the receiver each contains $120$ bytes. The delay between the sender and receiver is $5$ time units, and so the first segment arrives at the receiver at t $=6.$ The ACKs sent by the receiver at t $=6,7,8,10,11,12$ are shown. The TCP segments $($if any$)$ sent by the sender at t $=11,13,15,16,17,18$ are not shown

The segment sent at t$=4$ is lost, as is the ACK segment sent at t$=7$

What is the ACK value carried in the receiver$-$to$-$sender ACK sent at t $=10?$