please write each problem in the format: To find, Solutions, Answers. please rectangle the final answer for me Thanks

7. If (10111001)2 is an 8-bit one's complement number, what is the decimal equivalent? {{6 points}} a. 70 b. -57 C. -70 d. 185 8. If (10111001)2 is an 8-bit two's complement number, what is the decimal equivalent? {{6 points}} a. 71 b. 70 C. -70 d. -71