4 miles / 0.5 hour = 8 miles / 1 hour.
8 miles per hour.
I'm pretty sure that it's natural gas.
False because the third line of defense is specific by identifying the foreign antigen and activating the antibodies that can bind to the invaders and eliminating the spread
They must be non-toxic ie not chemicals that could poison the customers because of the potential risk of contaminating things which can come into contact with the food like say cutting boards, dishes, utensils, pots, pans and any other similar items.