Can you please repeat how many tonnes of blood the heart pumps in twenty four hours. ?

The heart pumps around fifty times per minute. It pumps about five litres of blood a minute. So if you times that by sixty for the amount of blood in an hour and then times it by 24 for the number of hour in a day, it's about 7500 litres of blood every single day. Blood is about 1 gram per centimetre cubed, which means it's a thousand grams per litre. That means that if you pump 7500 litres in a day, that's 7.5 tonnes of blood pumped around your body every single day.