Through which of the following ways can heat be transferred?
a.
by direct or indirect contact between objects at different temperatures
b.
only by direct contact between objects at different temperatures
c.
heat can never be transferred between objects.
d.
only by indirect contact between objects at different temperatures

The correct option is:

A) by direct or indirect contact between objects at different temperatures

Explanation:

Heat can be transferred in three different methods:

Conduction, Convection and Radiation

Conduction is heat transfer through direct contact between substances at different temperatures.

Convection is the heat transfer which takes place through air currents.

Radiation is the heat transfer that does not require contact between two objects.

Hence, heat transfer can take place through direct or indirect contact between objects at different temperatures.

if you mean hydrogen and oxygen then water is the product

since electrons are negative the answer is neagtaive