Need solution of all

Problem 1. Let A = 4 -4 -2 . 8-[382 5.] Find the following if they exist. If they do not exist, give reasons why. a.det (A) b. det (B) C. B-1 Problem 2. Answer the following questions using modular arithmetic. a.) What is the last digit of 37275387463972020 b.) What is the last digit of 7663387463972021 c.) What are the last two digits of 401062536599320 d.) What are the last two digits of 401062536500659 Problem 3. a.) Using the Euclidean Algorithm, find the ged of 78 and 30. b.) Are they relatively prime? How do you know? c.) Then, using the Extended Euclidean Algorithm, write the god as a linear combination of 78 and 30. d.) Solve 30x = 6 (mod 78)