Fill in the Blank(about triangles)

Hello everyone, please help me with this problem...Thank you...

1. In a right triangle the (a)________of the triangle intersect at a point on the hypotenuse, the (b)________intersect at a point inside the triangle, and the altitudes of the triangle intersect at a (c)______of the triangle.

2. An isosceles triangle has sides of length 5, 5, and 8.

(a) What is the length of the median to the base?

(b) When the three medians were drawn, the median to the base is

divided into segments with lengths ______ and ______.

Then solve this problems if you can...Thanks again...^^;;

1. Find the area of a rectangle with length 12 inscribed in a circle with

radius 7.5.

2. Find the area of a square with radius 9. (By the way, what is the radius

in the regular polygon?)

3. The areas of two circles are 100 pie and 36 pie. Find the ratio of their

radii and the ratio of their circumference.

(Have a nice day....~!!!!^0^*)