What physical properties of nylon and leather make them good materials to use for shoelaces? A. high density and low conductivity B. durability and flexibility C. hardness and durability D. low viscosity and flexibility.
Answer:
wavelength refers to the length of a wave from one peak to the next.the amplitude of a wave Is measured from the peak to the trough

Focal length = 15cm
Magnification = +4
Type of lens : <u>convex</u>
We have to find distance of object..
★ <u>Lateral Magnification :</u>
m = v/u
- v denotes distance of image
- u denotes distance of object
4 = v/u
v = 4u
★ Lens Formula :-
→ 1/v - 1/u = 1/f
Focal length of convex lens is taken +ve and that for concave lens is taken -ve.
→ 1/4u - 1/u = 1/15
→ -3/4u = 1/15
→ u = -45/4
→ u = -11.25 cm
∴ (D) is the correct answer
Answer:
I may be wrong but I think its 10.
Explanation:
Number of Protons - Atomic mass.