Why are the other three wrong

Use your knowledge of the binary number system to write each binary number as a decimal number. a) 1001 base 2= base 10 b) 1101 base 2 = base 10

Libby built a fence that was 56 \text { feet}56 feet long over 44 days. she built the same length of fence each day. how many inches of fence did libby build each day?

Hey everyone! this question is a challenge question. for 50 points if you wish. all you have to do is answer the correct it has to be correct, in under 50 seconds, and i will make you the ! you want to accept this challenge. i already know! i mean, it's 50 free points! here is the question: 11x2= answer this correct, you get two prizes. don't forget. you only have 50 seconds or it wont happen. get it correct in under 50 seconds! that's not bad. so stop reading this long thing and !