Which one of the following is the correct relation between Celsius (C) and Fahrenheit (F)?

Which one of the following statements is not correct?

Which of the following statement is correct?

If x is the temperature of a system in Kelvin and y is the temperature of the system in °C, then the correct relation between them is

Which one of the following heat transfers is an example of convection ?

Which one of the following regarding density of water at atmospheric pressure is correct ?