400gr is 0.4 kg
so 6*0.4=2.4 dollars
Answer: 400grams cost 2.4 dollars
By definition, an obtuse triangle has an obtuse angle (angle greater than 90 degrees). The 3 angles of a triangle always add up to 180 degrees. Since one of our angles is greater than 90 degrees, the other 2 have to add up to less than 90 degrees, so there can be NO RIGHT ANGLES.
4•3•2•1=24
4 ways to fill the spot for first class
3 ways to fill the spot for second class
2 ways to fill the spot for 3rd class
1 way to fill the spot for 4th class
The answer is 18 .
All you have to do is swich the numbers