Solutions

LM-C11-C-001

A 7-token sequence needs 7 recurrent updates.

LM-C11-C-002

Hidden size 64 means the hidden-state vector has 64 numbers.

LM-C11-C-003

Only one recurrent parameter set is used. It is shared across all 9 steps.

LM-C11-C-004

The unrolled graph has 6 steps.

LM-C11-C-005

Yes. BPTT is ordinary backpropagation applied to the unrolled recurrent graph.