The slide costs $2 each time you ride. $15/2 = 7.5 so you can ride it 7 times.
Mixing the two concentrations would give a new concentration which is in between 50 - 60% .
D. 63% cannot be obtained
After 4 hours there will be 64 000
3 - 32k
2-16
1-8
do you need exactly 50 000?
