A=pi r^2 which if the following equations can be used to solve for the radius (r)

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.

Find the missing variable for a parallelogram: a = latex: 32in^2 32 i n 2 h = b = 6.3 in (1in=2.54cm)

Javier bought a painting for $150. each year, the painting's value increases by a factor of 1.15. which expression gives the painting's value after 77 years?