Richard records the weight of his two pets in a table, as shown. after how many weeks were the pets the same weight? what was their weight at that time? pet 1 week weight (grams) 0 400 2 800 pet 2 week weight (grams) 0 500 2 700 a. at 1 week, they both weighed 600 grams. b. at 2 weeks, they both weighed 500 grams. c. at 3 weeks, they both weighed 650 grams. d. at 4 weeks, they both weighed 1,000 grams.