What is 4 8/9 divided by 2/3 in simplest form?

Can any one me with the answers to these questions asap?

Use circumcenter theorem to solve for the given values

In the field of thermodynamics, rankine is the unit used to measure temperature. one can convert temperature from celsius into rankine using the formula , what is the temperature in celsius corresponding to r degrees rankine? a. 9/5(c - 273) b. 9/5(c + 273) c. 5/9( c - 273) d. 5/9( c + 273)