Answer:
2. I don't know for sure, but I'm pretty sure it's 1.05x10^28
3. 5,600,000,000,000
4. 0.00000000021
5. 87,300,000,000,000,000
Step-by-step explanation:
2) Again, I'm not 100% sure, but I would say 1.05x10^28 because it's the only one with three digits while the other numbers have two digits
3 & 5) The way scientific notation works is that when you have a positive exponent (like 12 and 16) you move the decimal point to the right that amount of times. So for example, take 5.6E12 (E12 is the same thing as saying 5.6x10^12 btw) the exponent would be 12, so you move the decimal point over 12 times. If you want to double check that you have enough zeros, move the decimal point again, and if it ends up at the end of the number when you hit 12, then you're fine. If you hit 12 in the middle of the number, erase all zeros to the right of the decimal point, and if you hit the end too early, add more zeros until you get it right.
4) Now when you have a negative exponent (-10) you do the opposite of 3 & 5 and move the decimal point to the left that amount of times. In this case, you would move the decimal point 10 times to the left, and you can use the same trick as before to make sure you have enough zeros. I also don't know how nitpicky your teacher is, but I would make sure to add one more zero to the left of the decimal just to make sure (by this I mean getting a number like 0.0005 instead of .0005) because some teachers do want you to do that. I hope this explanation helped :)
