Two trains A and B moving on a horizontal trackwith velocities Va=(40+¡30)km/h and Vb=(25-¡50)km/h. Determine in polar form the velocity of A relative to B.

if you mean

then it's c. 8, -7/3

but if you mean

then it is

step-by-step explanation:

one of the most important purposes of surface treatment is to alter surface properties according to the requirement of specific applications. for example, hydrophobic coating has been utilized on windshield and eyeglasses. gold atom monolayer on substrate has become a popular surface bioconjugation strategy.  

5

step-by-step explanation:

3. 8,935,200 minutes

4. 227,040 feet