The questionnaire survey was conducted on 40 sixth graders in an elementary school.
The questionnaire was as for three subjects, language, mathematics (Sansue) and science, if they like it, mark o, if they do not like it, mark x.
The grand total of o was 100 and that of x was 20.
There was no pupil who marked x to all three subjects.
There are 35 pupils who marked o to mathematics.
Among these, there are two pupils who marked o only to mathematics and four students who marked x to mathematics and o to science. Answer the following questions.
(1) Find the number of the pupil who marked o only to language.
(2) Find the number of pupil at most who marked o to all three subjects.