How many 4 digit numbers can you write using only the digits 2 and 5? With each digit having only 2 possibilities, the answer is 2 to the 4th power, which is 16. The 4 is because there are 4 digits. Think about the binary numbers 0000 to 1111, t â¦ here are 2 possibilities for each digit.
The CEN Exam fee is $360...BUT DO NOT PAY THIS AMOUNT!!!! ENA members can get the discounted rate of $220 ($140 savings!). If you're NOT an ENA member, you have the option to join. . All you do is pay your first year's dues (most states it's $100) AND you pay the discounted exam rate like you're already a member!
Typical costs: An official perc test that meets all local requirements for a septic or drainage system permit can cost $100-$1,000 or more depending on site size and conditions. Some areas mandate a traditional perc test while others specify soil/site evaluation/testing with deep pits, but call it a perc test.