problems!??

Question

1)the expression radical 27 + radical 12 is equivalent to....A)5 radical 6 B)5 radical 3 C)radical 39 D)13 radical 3

2)In a class of 50 students, 18 take music, 26 take art, and 2 take both art and music. How many students in the class are not enrolled in either music or art? A)6 B)8 C)16 D)24

3)The set of intergers {3,4,5} is a Pythagorean triple. Another such set is A){6,8,12} B){8,15,17} C){6,12,13} D){6,7,8}

please help me!

Answer 1

1) 3 rad 3 + 2 rad3 = 5 rad 3

2) total students taking both = 42,
not enrolled in either = 50-42 = 8

3) B 64 + 225 = 289 = 17x17