Solve each of the following equations without at calculator.  

1. $20(1.05)x − 50 = 250$ 

   Step 1(a):

   $20(1.05)^x=300$

   Step 2(a):

   $1.05^x=15$

   Step 3(a):

   $\log(1.05^x)=\log(15)$

2. $3\log_2(x) + \log_2(27) = \log_5(125)$ 

   Step (b):

   $\log_2(x^3)+\log_2(27)=3$

3. $\ln(x) − \ln(x − 2) = 2$ 

   Step (c):

   $\ln\left(\frac{x}{x-2}\right)=2$