51.Which of the following are true regarding equinoxes ? (i) They occur on March 21st and Sept 23rd (ii) They depict equal days and equal nights on march 21st and Sept 23rd on all places of the earth. (iii) All places on the earth have equal temperature during equinoxes

52.Twelve constellations referred to as zodiac, are

53.Which of the following phenomenon gives an evidence for the spherical shape of the earth ?

54.The speed of rotation of the earth is

55.Mercator projection refers to