The shells close due to the two adductor muscles. It is their contraction that allows the shell to close. All clams (with the exception of the scallop) do not have eyes. However they do have a heart, kidneys, an anus and a mouth. These organs are always present, regardless of the size of a clam.
The average annual salary of a certified nurse midwife is $91,070. The highest paid nurse midwives earn around $119,690, while the lowest paid come in around $62,480 per year. The average hourly salary for certified nurse midwives ranges from $30.04 to $57.55 with the median at $43.08 per hour.
Certified Nurse Midwife Salary. The US Bureau of Labor Statistics (BLS) provides a detailed analysis of the salaries for certified nurse midwives as of 2015. Those in the top 10% earned an average salary of $132,370, while the national median for nurse midwives that year was $98,190. Shown here is the range between the median and top ten percent average salary and hourly pay rate for CNMs as of 2015 (US Bureau of Labor Statistics):