Thiết bị trao đổi nhiệt ngược chiều, nhiệt độ chất lỏng nóng vào là 310°C, ra là 115°c. Nhiệt độ chất lỏng lạnh vào là 25°c và ra là 68°c. Hãy tính độ chênh lệch nhiệt độ trung bình ∆t(m)

129.5 m

Explanation:

310 + 115 + 25 + 68 = 518

518 / 4 = 129.5 m

i think. Sorry if this is wrong

:)

Mass is the amount of matter in an object, and weight is the downward pull on an object due to gravity.

Explanation:

The amount of matter contained in an object is known as mass. The mass remains same where ever the object is taken. It measured in grams,  kilograms, slug etc.

1 slug = 14.6 kg

Weight is the downward pull on an object due to gravity. Hence, the weight is not same on different planets. weight is the product of mass and acceleration due to gravity. It is measured in Newtons, pounds etc.

1 N = 1 kg.m/s²

1 pound = 4.45 N

Therefore, the correct statement which summarizes the difference between mass and weight is Mass is the amount of matter in an object, and weight is the downward pull on an object due to gravity.