1.Which functions represent exponential decay?

f(x)=5⋅(1/8)x
f(x)=(1/5)⋅3x
f(x)=5⋅(2/3)x
f(x)=4⋅(1/5)x
f(x)=2⋅5x
f(x)=(1/3)⋅2x

2. Caleb deposits $500 in an account that pays him 2% annual interest compounded quarterly. Which equation represents the account balance A after t years?
a.A=500⋅(1.005)4t
b.A=500⋅(1.005)t
c.A=500⋅(1.02)t
d.A=500⋅(1.02)4t

3.What is the inverse of f(x)=3x3

4. (8)4x=1/24 round to the nearest hundredth