Given the single character string str ="d ". 1. Compute sha-256 value of str in Hex with no colons separating the hex values. 2. The sha-256 value of str forms a leaf node in a larger Merkle tree at index 3 . Given the merkle branch below associated with this leaf node calculate the Merkle root 2e7d2c03a9507ae265ecf5b5356885a53393a2029d241394997265ala25aefc662af5c3cb8da3e4f25061e829ebeea5c7513c54949115blacc225930a90154dad6cf2ad3f66d0599d97346c6aad0f1081913df26d8b80e4ffa052e0alf8391c62e15ecd6e7d77f95c9275a7cc4cf9338518ef7b9490097510f994d8111ccf1d8 3. Write the root in the format used by Bitcoin proof of work