Me with questions 30 and 32 with work shown

Iknow its nothing to do with education, but what type of thing should i wrote here? ? : ) its for mcdonald's btw.

Write 5 in the form of a/b using integers to show it as a rational number

Find the radius of a circle that has a circumference of 16. the formula for the circumference of a circle is c = 2tr, where r is the radius and c is the circumference. the equation solved for r is r = c over 2π. r=4 r= 8 r=12 r= 16