A sample of a population in a nervous t. grant. Amphoe Damnoen Saduak, Ratchaburi that consent to participate in research conducted by arise from a voluntary participant research. Which is derived from the calculation of sample size using the formula of the Yamane (1973), based on the level of confidence and a certain amount of populous (Chai tantayaporn, 2550 (2007)) as follows:
การแปล กรุณารอสักครู่..