How do i convert 140 degrees into a radian?

What is the area of the triangle 10 13 12

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

Which of the following is a solution of z^6 = 64i? 2(cos105° + isin105°) 2(cos120° + isin120°) 2(cos135° + isin135°) 8(cos15° + isin15°)