Vanessa now wants to compare productivity across periods. She sees that Betty the brownie baker worked 50 hours this week and baked 215 brownies. The week before, Betty worked for 40 hours and baked 140 brownies. a. Calculate Betty's productivity for this week and last week. (Round your answers to 2 decimal places.) This week's productivity 4.3 Units / hr Last week's productivity 3.5 Units / hr b. Is Betty's productivity the same in these two weeks, or does it increase (or decrease)? (Round your intermediate calculations and final answer to 2 decimal places. Omit the "%" sign in your response.) Betty's productivity by %