Help i will mark brianliest

Using the side-splitter theorem, daniel wrote a proportion for the segment formed by luke segment de. what is ec?

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

See attachment below and find the equivalent of tan(∠qsr)