Questions

Normal Gas welding use oxygen-acetylene.

Depending on what materials you are welding, there are some more options that might be used.

For example - MIG/TIG use Argon, MAG use an argon-something mix.

Nixon

Q = mc∆T refers to Specific Heat formula.

When heat energy is added to a substance, the temperature will change by a certain amount.

The relationship between heat energy and temperature is different for every material, and the specific heat is a value that describes how they relate.

Q = mc∆T

Q = heat energy (Joules, J)

m = mass of a substance (kg)

c = specific heat (units J/kg∙K)

∆T = change in temperature (Kelvins, K)

From the given data,

1 + 9 + 8 = 1

ONE + NINE + EIGHT

Consider the first letters and join them viz O N E = 1

So, now consider 2 + 8 + 9 in similar way

TWO+EIGHT+NINE

First letters are T E N = 10

2 + 8 + 9 = 1⃣0⃣