Identify each function as linear or exponential and explain why it is either linear or exponential. Check the function growth at \(x=0, 1\) and \(2\).
1. \(f(x)=3x\)
2. \(f(x)= \left( \dfrac{2}{3} \right) ^x\)
3. \(f(x)=-4^x\) and \(f(x) = 4^x\)
4. \(f(x)=7(2)^x\)
5. \(f(x)=7(0.5)x\)
