text: import { calculateCost } from "../libs/billing-lib";
  
  test("Lowest tier", () => {
      const storage = 10;
      const cost = 4000;
      const expectedCost = calculateCost(storage);
  
      expect(cost).toEqual(expectedCost);
  });
  
  test("Middle tier", () => {
      const storage = 100;
      const cost = 20000;
      const expectedCost = calculateCost(storage);
  
      expect(cost).toEqual(expectedCost);
  });
  
  test("Highest tier", () => {
      const storage = 101;
  
      const cost = 10100;
      const expectedCost = calculateCost(storage);
  
      expect(cost).toEqual(expectedCost);
  });