*A race car driver must average 200 km/hr for four laps to qualify for a race. Because of engine trouble, the car averages only 170 km/hr over the first two laps. What average speed must be maintained for the last two laps? The answer from my teacher is 243 km/hr but I don’t know how to solve to get that answer? Please help!!!

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

talk back to him about the sport and show him your expertise or leave the room

in most common fires, oxygen is needed for an oxidation reaction to takes place. the combination of oxygen with any element as fuel can create fire and combustion will occur especially if wood, light materials and other combustible things are combine with oxygen.