# NPTEL Blockchain and its Applications Week 3 Assignment Answers 2024

## NPTEL Blockchain and its Applications Week 3 Assignment Answers 2024

1. Inspect and explore block #828070 using this link to solve the below question. What is the hash of the previous block for Bitcoin block #828070?

a. 0000000000000000000246e18870310474e18acbd1fd8453abbb6f367174816f
b. 00000000000000000001d857c22ab5211e2173e4f970eb15f04f64e692587aa
C. 000000000000000000034511894ee97dfa62803bb338335a12e40f6e5a45172
d. 00000000000000000002c2c0e69e794d1968382626109ed1d6441020105e7d
4e

`Answer :- For Answer Click Here`

2. Which of the following Bitcoin scripts will generate a TRUE outcome?
a. scriptSig: < sig>
scriptPubkey: < pubkey> OP_DUP OP_HASH256
OP_EQUAL OP_VERIFY OP_CHECKSIG
b. scriptSig:
scriptPubkey: OP_HASH160 < pubkeyhash> OP_EQUAL
c. scriptSig:
scriptPubkey: OP_EQUALVERIFY
d. scriptSig:
scriptPubkey: < pubkey> OP_CHECKSIG

A. a, b, c
B. C, d
C. a. b, d
D. a, c, d

`Answer :- For Answer Click Here`

3. In the Bitcoin block header, the block identifier is calculated

a. Using SHA256 on the current block header
b. Using Double SHA256 on the previous block hash
c. Using Double SHA256 on the Difficulty bits
d. Using Double SHA256 on the current block header

`Answer :- For Answer Click Here`

4. If the six-byte difficulty bits in the hexadecimal form are 0x1a05f20881ab, and the
target value is calculated using X* 2(Y), what are the values for X and Y
respectively?

a. X = 0x5f20881ab, Y = 0x1a
b. X = 0x1a05f2, Y = 0×0881ab
c. X = 0x1a05f2, Y = 0x18
d. X = 0x5f20881ab, Y = 0×1a0

`Answer :- `

5. DLT can be used to maintain financial information only.

a. False
b. True

`Answer :- `

6. Which one of the following opcodes is needed to remove the second-to-top stack
item?

a. OP_DELETE
b. OP_2POP
c. OP_DEQUE
d. OP_NIP

`Answer :- For Answer Click Here`

7. Bitcoin Scripting Language:

a. Not Turing Complete
b. Supports Cryptography
c. Queue Based
d. Supports infinite time/memory

`Answer :- `

8. Permissioned blockchain is regarded as more secure than open blockchain as the
participants are known beforehand and pre-authenticated

a. True
b. False

`Answer :- `

9. What is nonce?

a. The transaction ID number
b. A miner ASIC chip array
c. The generator point used in elliptic curve cryptography
d. The number miners run through to generate a correct hash

`Answer :- `

10. Which of these fields is present in a Bitcoin block summary?

a. Nonce
b. Gas Used
c. Gas Limit
d. Private Key of the Sender

`Answer :- For Answer Click Here`