Simplify (6x2 − 3 + 5x3) − (4x3 − 2x2 − 16). (1 point) a 2x3 − x2 + 21 b −2x3 + x2 − 21 c x3 + 8x2 + 13 d −x3 − 8x2 + 13

Two cities a and b are 1400km apart and lie on the same n-s line. the latitude of city a is 23 degrees. what is the latitude of city b. the radius of the earth is approximately 6400km.