A. Mercury and Bromine
B. Carbon and helium
C. Nitrogen and Hydrogen
D. Oxygen and Neon

A. Metre, litre and gramme
B. Centimetre, kilograms and metric
C. Kilogram, mass and energy
D. Kelvin, cd and mole

A. Electron
B. Neutron
C. Proton
D. All of Above

A. Galileo
B. Albert Einstein
C. Issac Newton 
D. Hubble

A. Carbon
B. Helium
C. Methane
D. Nitrogen

A. -40 degree
B. 40 degree
C. -10 degree
D. 10 degree

The formulas for converting between degree Celsius and degree Fahrenheit are:
°F = (°C * 9/5) + 32
°C = (°F – 32) * 5/9
To find the temperature when both are equal, we use an old algebra trick and just set ºF = ºC and solve one of the equations.
°C = (°C * 9/5) + 32
°C – (°C * 9/5) = 32
-4/5 * °C = 32
°C = -32 * 5/4
°C = -40
°F = (°F * 9/5) + 32
°F – (°F * 9/5) = 32
-4/5 * °F = 32
°F = -32 * 5/4
°F = -40
So the temperature when both the Celsius and Fahrenheit scales are the same is -40 degrees.