Which of the following expressions is equivalent to 1/a^-5 a. 1/a^5 b. a^5 c. a ^-5 d. -1/a^5

To make that negative exponent positive, we have to put it under a 1.  It's already under a 1, but we have to put it under another 1! Like this: .  That's like .  When we divide a fraction by a fraction, we bring up the bottom one and flip it to multiply to give us this expression: , which of course simplifies to just

Iam not sure , but probably 750 or 7.5