The population of a city increases by 4,000 people each year. In 2025, the population is projected to be 450,000 people. What is an equation that gives the city's population p (in thousands of people) x years after 2010?
a. p=4x+50
b. p-450=4(x-15)
c. p-15=4(x-450)
d. p=4x+15
B?