Which expression is not equivalent to 1/343? a. 7^4 x 7^-7 b. 7^7 x 7^-10 c. 7^2 x 7^-5. d. 7^-5 x 7^2

Someone answer asap for ! the following statements are true about the coins calvin and sasha have collected. * calvin and sasha has the same amount of money. * calvin has only quarters. * sasha has dimes, nickels, and pennies * calvin has the same number of quarters as sasha has dimes. * sasha has $1.95 in coins that are not dimes. exactly how many quarters does calvin have?