During an early-morning period, the following appliances are used:
• Geyser: 2.0 kW, 06:00–07:00 h
• Microwave oven: 1.2 kW, 06:30–07:00 h
• Electric iron: 1.0 kW, 06:45–07:15 h
What is the maximum (peak) load on the household supply during this interval?
a) 3.2kW
b) 4.2kW
c) 2.5kW
d) 4.0kW