Answer:
A
Explanation:
Coal is majorly used to produces electricity. The coal is ignited and the heat produced used to heat water to steam. The steam is then used to drive turbines with a dynamo effect to produce electricity. Turning off lights when not in use reduces the demand for electricity hence reducing the amount of coal needed to meet this demand.
Other ways to conserve energy is using bulbs with low energy demand - such as LEDs - and improving natural lighting indoors.
You can further understand a text if you ask questions.
Heart disease affects the cardiovascular system by plaque building up on the artery walls narrowing them making it harder for blood to flow through which could lead to heart attack or probably stroke if the plaque blocks it entirely or maybe almost entirely.
Heart disease may also affect our nervous system for there is higher risk to stroke and it is due to limited flow of blood to the brain and may lead to heart failure which may happen with heart disease that puts the stress on the brain and nerves.
The digestive system is affected by heart disease that causes the system to not get the right amount of oxygen and the nutrients that it needs from the blood.
