Users cannot communicate with a remote site in a network. Looking at the Cisco router output below, which of the following are likely causes of this problem? Router$-$A# show interface serial$0$Serial$0$ is down, line protocol is down Hardware is HD$64570$ Internet address is $10\mathrm{.}2\mathrm{.}3\mathrm{.}5/30$ MTU $1500$ bytes, BW $1544$ Kbit, DLY $20000$ usec, rely $255/255,$ load $68/255$ Encapsulation HDLC$,$ loopback not set, keepalive set $(10$ sec$)$ Last input $00$:$00$:$00,$ output $00$:$00$:$00,$ output hang never Last clearing of "show interface" counters never Input queue: $0/75/0($size$/$max$/$drops$)$; Total output drops: $7082$ Queueing strategy: weighted fair Output queue: $0/64/7082($size$/$threshold$/$drops$)$ Conversations $0/205($active$/$max active$)$ Reserved Conversations $0/0($allocated$/$max allocated$)5$ minute input rate $754000$ bits$/$sec$,307$ packets$/$sec $5$ minute output rate $413000$ bits$/$sec$,96$ packets$/$sec $744279053$ packets input, $2083398797$ bytes, $0$ no buffer Received $0$ broadcasts, $0$ runts, $1$ giants $1372$ input errors, $1094$ CRC$,0$ frame, $0$ overrun, $0$ ignored, $277$ abort $456736163$ packets output, $3829305470$ bytes, $0$ underruns $0$ output errors, $0$ collisions, $7$ interface resets $0$ output buffer failures, $0$ output buffers swapped out $9$ carrier transitions RTS down, CTS down, DTR down, DCD $,$ DSR down