While in Europe, if you drive 103 km per day, how much money would you spend on gas in one week if gas costs 1.10 euros per liter and your car's gas mileage is 35.0 mi/gal

see earlier answer

at right angles to each other

blue light is scattered in different directions by the tiny molecules of air. blue is scattered more than other colours because it has a shorter distance to travel which results in smaller waves. this is why we see a blue sky most of the time.