The function f(x) = 4(3)^x represents the growth of a dragonfly population every year in a remote swamp. Erin wants to manipulate the formula to an equivalent form that calculates four times a year, not just once a year. Which function is correct for Erin's purpose, and what is the new growth rate?
f(x) = 4(3)^x; growth rate 300%

f(x) = 4(3)^x, growth rate 4%

f(x) = 4(1.32)^x; growth rate 4%

f(x) = 4(1.32)^4x; growth rate 32%

Question

The function f(x) = 4(3)^x represents the growth of a dragonfly population every year in a remote swamp. Erin wants to manipulate the formula to an equivalent form that calculates four times a year, not just once a year. Which function is correct for Erin's purpose, and what is the new growth rate? 
f(x) = 4(3)^x; growth rate 300% 

f(x) = 4(3)^x, growth rate 4% 

f(x) = 4(1.32)^x; growth rate 4% 

f(x) = 4(1.32)^4x; growth rate 32%