Me with number 2. i already have number 4. and leave a description on how to do it! you!

Suppose the radius of a circle is 16. what issuppose the radius of a circle is 16. what is its circumference its circumference

Kelly is a salesperson at a shoe store, where she must sell a pre-set number of pairs of shoes each month. at the end of each work day the number of pairs of shoes that she has left to sell that month is given by the equation s=300-15x , where s is the number of pair of shoes kelly still needs to sell and x is the number of days she has worked that month. what is the meaning of the number 300 in this equation

Plz hurry evaluate the expression a+b where a=8 and b=19