Which statement best identifies the point of view of someone who lived through the Pax Romana period of the Roman Empire? A Romans were involved in wars over land with China
B There were no major wars or rebellions, and trade increased
C Julius Caesar was assassinated
D Trade decreased between the Roman

(help please :)

Shari is trying to decide how she should use her cash birthday gifts. her choices are new clothes, a concert ticket, or donating the money to her favorite charity. shari decides to donate the money. the value given up by not choosing both the clothes and the concert ticket is called a . a.) trade-off b.) opportunity cost c.) retail price