Guys please help me!

What is 100,000 times 1/100,000, using the standard method of multiplication? write the answer as 10 to a power.

What is the equivalent fraction for the following fraction using 5 as the multiplier? 1/2

Harry owes the bank money. to repay his debt, he paid $150 back to the bank each month. after 10 months, his remaining debt was $6900. what was the original amount of harry's debt? how long did it take harry to pay back his entire debt?