Introduction:
Logarithm is a mathematical function used to find the exponent to which a given base must be raised to produce a given number. In this problem, we need to find the value of log 1.8*10^-5.

Step 1: Identify the base and exponent:
The given number is 1.8*10^-5. Here, the base is 10 and the exponent is -5.

Step 2: Express the number in scientific notation:
1.8*10^-5 can be expressed in scientific notation as 0.000018.

Step 3: Apply the logarithm formula:
Logarithm formula is: logb a = log a / log b. Here, b is the base and a is the number we want to find the logarithm of.

Therefore, log 1.8*10^-5 = log (0.000018) / log 10. Since log 10 = 1, we can simplify the expression to:

log 1.8*10^-5 = log (0.000018)

Step 4: Evaluate the logarithm:
We can evaluate the logarithm using a calculator or a table of logarithm values.

Using a calculator, we get: log 1.8*10^-5 = -4.744

Therefore, the value of log 1.8*10^-5 is -4.744.

0.2