Ans:(-16)
assume addresses start with $2000$ for the first instruction.
$2000---\text{add }R2,R3,R4$
$2004---\text{sub }r5,r6,r7$
$2008---r1,r9,r10$
$2012---\text{beq } r1,$offset //pc after instruction fetch of this instruction will be $2016$,
and branch target is $2000,$offset will be $(2016-16)=2000$
$2016$------next instruction