How does the Doppler effect related to the universal expanding?

The Doppler effect doesn't just apply to sound. It works with all types of waves, which includes light. Edwin Hubble used the Doppler effect to determine that the universe is expanding. Hubble found that the light from distant galaxies was shifted toward lower frequencies, to the red end of the spectrum. This is known as a red Doppler shift, or a red-shift. If the galaxies were moving toward Hubble, the light would have been blue-shifted.

Heat required to melt 26.0 g of ice at its melting point is 8.66 kJ.

Explanation:

Number of moles of water in 26 g of water: 26× moles

                                                                      =1.44 moles

The enthalpy change for melting ice is called the entlaphy of fusion. Its value is 6.02 kj/mol.

we have relation as:

                                           q = n × ΔH

where:

q  = heat

n  = moles

Δ H  = enthalpy

So calculating we get,

                                        q= 1.44*6.02 kJ

                                        q= 8.66 kJ

We require 8.66 kJ of energy to melt 26g of ice.