PLEASE HELP!

Your class hopes to collect at least 325 of food for the annual food drive. There were 135 cans donated the first week and 89 more the second week.
Part 1: Write an equation that describes this situation. Let c represent the number of cans of food that must be collected by the end of the third week for your class to meet or surpass its goal.
Part 2: How many cans are needed to meet or surpass the goal?