Math Graph Que

Please answer these two questions and the three attached questions ASAP. 
1. Find the length of the unknown side of the right triangle with sides a, b, and c, where c is the hypotenuse. Give an exact answer and a two-decimal-place approximation. 
b=5, c=15
The exact answer is ________.
(Simplify your answer. Type an exact answer using radicals as needed.)
The two-decimal-place approximation is _________.
(Round to two decimal places as needed.)
2. Graph the set of numbers on a number line. (Please use separate number lines to show each number.)
A. Graph the point -4
B. Graph the point 2
C. Graph the point 1/2
D. Graph the point -1/3