One day Ram went to his home town during Dussehra vacation. During his excursion, he noted the four places Temple, TV tower, Mall and School, then he tried to locate all the places using graph sheet by taking his position at origin. He marked A, B, C and D for school, TV Tower, Temple and Mall respectively on the graph sheet by taking scale as 1 Unit = 1 km as shown below.
Find the co-ordinates of C.