For those interested, here are some cosmology calculators where you can plug in different parameters and see the answers,
https://ned.ipac.caltech.edu/help/cosmology_calc.html
Measuring the redshifts and spectra for remote objects is critical measurements. Some amateurs today can measure the redshifts of some quasars in their backyards
. Special Relativity and General Relativity equations used.
"Using the Hubble Space Telescope, the H0LiCOW team studied the light from six quasars between 3 billion and 6.5 billion light-years away from Earth. As the quasars' black holes gobbled material, their light would flicker.
The intervening gravitationally lensing galaxy bent each quasar's light, and so the quasar's flickering arrived at Earth at different times depending on what path it took around the foreground galaxy, Chen said. The length of the time delay provided a way to probe the expansion rate of the universe, he added.
H0LiCOW was able to derive a value of the Hubble constant of 50,331 mph per million light-years (73.3 km/s/Mpc), extremely close to that provided by Cepheid variables but quite far from the CMB measurement. "