An LCD screen is purchased to be used in the manufacturing of a digital watch. The Standard Price (SP) for the LCD screen used is $40.00. During the month of February, 30,000 screens were purchased and used. The materials price variance was $7,500 unfavorable. The standard number of screens allowed for the actual number of watches manufactured during the period was 24,000 screens. The actual purchase price of each LCD screen is closest to $40.40 per LCD screen 537.50 per LCD screen. S42.50 per LCD screen. $3.20 per LCD screen