Which statement best describes the relationship between an object's density and its index of refraction? A. As the physical density of the substance increases, the refractive index increases.

B. As the optical density increases, the refractive index increases

C. As the mass of the object increases the refractive index decreases

D. As the mass per unit volume of the substance increases, the refractive index decreases

e) none of the above answers are correct

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards