Multiply. (2.5×10−8)(9×10−10) express your answer in scientific notation. all of the ones with - is to the power of a. 2.25×10−17 b. 2.25×10−16 c. 2.25×10−19 d. 2.25×10−18

Plz hurry evaluate the expression a+b where a=8 and b=19

You have 37 coins that are nickels, dimes, and pennies. the total value of the coins is $1.55. there are twice as many pennies as dimes. find the number of each type of coin in the bank.

What 620000 divided by 10 to the third power