Help with a High School rule

[HLin NC]

The OP says in both instances that the A player was "downed". The Rule 7 case play I posted that rules TD is identical.

Where in the world does it state that a player must be "tackled" to stop forward progress? The rule and case book both say "contact or contacted". "Tackle" actually has no definition under Federation rules.

If B55 hits, tackles, contacts, or "lights up" runner A20 at the A35 yard line and knocks him back and he is downed at the A32 yard line, where are you going to spot the ball?

If an A receiver possesses the ball in the air at the 50 yard line and then B knocks him back and to the ground and downed or out of bounds at the 47, where are you going to spot the ball?

Here's a hint:
SECTION 15 FORWARD PROGRESS
ART. 1 . . . Forward progress is the end of advancement of the ball in a runner’s possession or the forward-most point of the ball when it is fumbled out of
bounds toward the opponent’s goal and it determines the dead-ball spot.
ART. 2 . . . When an airborne player makes a catch, forward progress is the
furthest point of advancement after he possesses the ball if contacted by a defender.