Trey has answered 15 emails, this is 20% of emails he must answer. How many emails does he need to answer?

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

What are the equivalent ratios for 24/2= /3= /5.5=108/ = /15

Find the power set of each of these sets, where a and b are distinct elements. a) {a} b) {a, b} c) {1, 2, 3, 4} show steps