The teachers in the survey had an average of 16 years' experience.
They have to guess which answer was given by most of the people involved in the survey.
In a 1995 survey, the number was just 25 percent.
The companies in the survey spent a total of $1.1 billion on commercial air services last year.
The numbers are similar to those found in the first survey 10 years ago.
On the other hand, they said television took more effort now than it did in the 1975 survey.
That was down from 23 percent in the last survey.
That's up from 40 percent in a similar survey last year.
Check out what women had to say in a 2004 survey.
Staff members said in a survey that they would never go back to the old system.