David Upton is President of Upton Manufacturing, a producer of Go-Kart tires. Upton makes 1000 tires per day with the following resources: Labor: 500 hours per day @ $20 per hour Raw material: 25,000 pounds per day @ $3 per pound Energy: $5,000 per day Capital: $10,000 per day (a) What is the labor productivity for these tires at Upton Manufacturing? (b) What is the multifactor productivity for these tires at Upton Manufacturing? (c) What is the percent change in multi-factor productivity if Upton can reduce the energy bill by $1,500 without cutting production or changing any other inputs?