Which function has an inverse that is a function?

a. b(x) = x2 + 3
b. d(x) = –9
c. m(x) = –7x
d. p(x) = |x|

Ihave a 69 and an 82. the 69 is worth 40% of my grade and the 82 is worth 15%. can someone tell me my current average grade.

The weight of an object in the water is 7% of its weight out of the water. what is the weight of a 652g object in the water?

Bobs burgers bam has a special deal of 4 hamburgers for $6. at that rate, how much should it cost to buy 3 hamburgers?