Which expression is equivlent to (2^3)^-5?

1/2^15

1/2^8

2^8

2^15

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 can each term of the equation be multiplied by to eliminate the fractions before solving? x – + 2x = + x 2 6 10 12

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25