The rate of change of the volume of a snowball that is melting is proportional to the surface area of the snowball. suppose the snowball is perfectly spherical. then the volume (in centimeters cubed) of a ball of radius r centimeters is 4/3 πr3. the surface area is 4πr2. set up the differential equation for how r is changing. then, suppose that at time t = 0 minutes, the radius is 10 centimeters. after 5 minutes, the radius is 8 centimeters. at what time t will the snowball be completely melted?

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations:

b. 153 students do not participate in sports and seventy-five 12th graders were surveyed

answerim :

n

step-by-step explanation:

im not sure but my dad knows