If you have an infinite number of red, blue, yellow, and black socks in a drawer, how many socks must you pull out of the drawer to guarantee that you have a pair?

I’m really confused and need your assist me with this question i’ve never been taught

What is the least common multiple for 6 and 8? what is the least common multiple for 4 and 12 ? what is the least common multiple for 11 and 12? what is the least common multiple for 3 and 6?

Given the expression (7 ? 4i) ? (2 + 6i), perform the indicated operation and write the answer in the form a + bi.