I think your question is incomplete because the distance between destination and departure point isn't given in the question
Alvin (DSV-2) is a manned deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Massachusetts. The vehicle was built by General Mills' Electronics Group[2] in Minneapolis, Minnesota. Named to honor the prime mover and creative inspiration for the vehicle, Allyn Vine, Alvin was commissioned on 5 June 1964. The submersible is launched from the deep submergence support vessel RV Atlantis (AGOR-25), which is also owned by the U.S. Navy and operated by WHOI. The submersible has made more than 4,400 dives, carrying two scientists and a pilot, to observe the lifeforms that must cope with super-pressures
Answer: 0.72 grams
Explanation: Mass can be extracted from the formula of density. D=M/V where D is density and V is volume. Therefore:
18 g/cm^3 = M(25 cm^3) --> Divide by 18g/cm^3 by 25 cm^3 to isolate mass. --> <u>0.72 =M </u> --> Now, to find out which unit you need to use for mass, just look at the density. You can see it is in g/cm^3, and cm^3 was already used for the volume. Thus, gram units are left, so that will be the unit needed, making the final answer 0.72 grams. Hope this helps :)
Answer: a. 53cm b. Diverging c. 0.02dioptres
Explanation:
Since the person in question cannot see far object clearly, it shows that the individual is suffering from myopia (short sightedness).
If the object distance (u) is 53cm. for the person to be able to see far way, it means the image must be at infinity. This shows image distance v is infinity. Using the lens formula
1/f = 1/u+1/v
1/f = 1/53 + 1/Infinity
1/f = 1/53 + 0
f=53cm
b) The lens used is concave lens (diverging lens) to diverge all rays outwards
c) Power of a lens P will be 1/53.
P = 0.02dioptres
The first person went further. s = d/t
Hope this helps you out APHDenmark! :D