A problem about cryptography:

Let h be a cryptographic hash function from h: {0, 1}* rightarrow {0, 1}^n. State whether the following encryption schemes are semantically secure? Explain your answer. To encrypt a n bit long string m Element {0, 1}^n, send (m h (11 middot middot middot 11} n)). To encrypt a n bit long string m Element {0, 1}^n, pick a random n bit string r leftarrow^random {0, 1}^n and output the cyphertext (r, h (r) m). To encrypt a 2n bit long string m Element {0, 1}^2n. We first parse m = m_1 || m_2 with m_1 and m_2 both n bit long strings. Then pick a random n bit string r leftarrow^random {0, 1}^n and output the cyphertext (h (r) m_1, h (r) m_2.) Let h be a cryptographic hash function from h: {0, 1}* rightarrow {0, 1}^n. State whether the following encryption schemes are semantically secure? Explain your answer. To encrypt a n bit long string m Element {0, 1}^n, send (m h (11 middot middot middot 11} n)). To encrypt a n bit long string m Element {0, 1}^n, pick a random n bit string r leftarrow^random {0, 1}^n and output the cyphertext (r, h (r) m). To encrypt a 2n bit long string m Element {0, 1}^2n. We first parse m = m_1 || m_2 with m_1 and m_2 both n bit long strings. Then pick a random n bit string r leftarrow^random {0, 1}^n and output the cyphertext (h (r) m_1, h (r) m_2.)