Prove or Disprove: for All Integers $$a , b , c , d \text {, if } a \mid b \text { and } c \mid d \text {, then } ( a c ) \mid ( b + d ) \text {. }$$

Q10: Find the prime factorization of 111111.

Q53: Solve the linear congruence 54x ≡ 12

Q54: Use the Euclidean Algorithm to find gcd(900,

Q55: Use the Euclidean Algorithm to find gcd(128,

Q56: Prove or disprove: For all integers

Q57: Prove or disprove: For all integers

Q59: Explain in words the difference between

Q60: determine whether each of the following

Q62: Prove or disprove: <span class="ql-formula"

Q63: List all positive integers less than 30