<image>In a school, 800 senior year students participated in a 100-meter test, with all results ranging from 12 seconds to 17 seconds. A sample of 50 students was taken, and the test results were divided into five groups as follows: the first group [12,13), the second group [13,14), ..., and the fifth group [16,17]. The frequency distribution histogram based on this grouping is shown in the figure.
(1) If scores less than 13 seconds are considered excellent, find the number of students in the sample who achieved excellent scores in this 100-meter test;
(2) Estimate the number of students among the 800 senior year students whose scores belong to the third group;
