Answer:
288J
Step-by-step explanation:
recall the formula for kinetic energy
KE = (1/2) mv²
where m is the mass (= 4kg) and v is the velocity(=12 m/s)
hence
KE = (1/2) (4)(12)² = 288J
If it is marked down 25% and 25% equals 25/100 then you simply take 39.59 x 25/100
39.59 x 25/100 = 9.90
and then you subtract that from the original price
39.59 - 9.90 = $29.69
after it is marked down, the price is $29.69
They are always on a coplanar
The interior of a triangle = 180°
So 180° - 85° -50° = 45°
c. 45 degrees