A young child is flying a kite which is at height of 50 m. The wind is carrying the kite horizontally away from the child at a speed of 6.5 m/s. How fast must the kite string be let out when the string is 130m ?

 Evaluate the determinant given below, where 𝜔 is a cube root of unity. 
1 𝜔 𝜔2
𝜔 𝜔2 1
𝜔2 1 𝜔