what is the difference and similarity between a pentagonal prism and a pentagonal pyramid?

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?

The population of a small rural town in the year 2006 was 2,459. the population can be modeled by the function below, where f(x residents and t is the number of years elapsed since 2006. f(t) = 2,459(0.92)

What is negative 3/9 times negative 2/8 ?