Ineed on this i don't know nothing

Peaches cost $4.29 per pound. find the cost of two and a quarter pounds of peaches.

An assembly consists of two mechanical components. suppose that the probabilities that the first and second components meet specifications are 0.87 and 0.84. assume that the components are independent. determine the probability mass function of the number of components in the assembly that meet specifications. x

17 in long 1.3 ft wide and 8in high what is the volume