10.一条信息可通过如图的网络线由上(A点)往下向各站点传送.例如信息到b2点可由经a1的站点送达,也可由经a2的站点送达,共有两条途径传送.则信息由A点到达d3的不同途径共有( )
0 157528 157536 157542 157546 157552 157554 157558 157564 157566 157572 157578 157582 157584 157588 157594 157596 157602 157606 157608 157612 157614 157618 157620 157622 157623 157624 157626 157627 157628 157630 157632 157636 157638 157642 157644 157648 157654 157656 157662 157666 157668 157672 157678 157684 157686 157692 157696 157698 157704 157708 157714 157722 199269
A. | 3条 | B. | 4条 | C. | 6条 | D. | 12条 |