#1 B 1/10 B13. The 10-yard penalty is enforced from the spot of the interception, B's 3. The momentum exception applies. The ball remains behind B's goal line in team possession. Player possession is not required.
#2 A 3/3 A47; Ready. The pass was touched by A82 behind the neutral zone. By rule, the pass did not cross the neutral zone. Thus, the penalty does not carry a first down. The 10-yard penalty is enforced from the previous spot, A's 37.
#3 Touchdown. B try A3. A14 throws an illegal forward pass from A's 26. B55 does not foul since the pass is not a legal forward pass. B55 may push A88 but may not pull A88 to get to the ball. It would also be a touchdown if this was a fourth down play.