text: const {mphToKmph} = require('./_30s.js');
  
  test('mphToKmph is a Function', () => {
    expect(mphToKmph).toBeInstanceOf(Function);
  });
  test('Returns kph from mph.', () => {
    expect(mphToKmph(10)).toBe(16.09344000614692);
  });
  