If x, y, and z are positive integers and 3x = 4y = 7z, then the least possible value of x + y + z is (A). 49
(B). 33
(C). 40
(D). 84
(E.) 61
I think it's E, but any thoughts??

The graph below could be the graph of which exponential function?

Rewrite the following without an exponent. (5/8)-1

Jackie purchased 3 bottles of water and 2 cups of coffee for a family for $7.35. brian bought 4 bottles of water and 1 cup of coffee for his family for $7.15. how much does each bottle of water cost? how much does each cup of coffee cost? i need this done