Answer:
15m/s
Explanation:
add the two speeds and divide by 2
10+20=30
30/2=15
Answer:
Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.
Explanation:
Smart Metering is a technology encouraging end-use energy efficiency. Smart Meters can give consumers clear and comprehensive information about their energy consumption and, giving them better information, can help consumers to become more energy efficient.
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