Which angle measure in the triangle shown is the largest?

What term best describes a line ans a point that lie in the same plane

Evaluate the following expression 1/3^2

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.