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(1) A "gry" is an old English measure for length, defined as 1/10 of a line, where "line" is another old English measure for length, defined as 1/12 inch. A common measure for length in the publishing business is a "point", defined as 1/72 inch. What is an area of 0.75 gry2 in terms of points squared (points2)?

I do (0.75 gry) (1line/10gry) (6pts/line)= 0.45 points (left out squares for simplicity) But this answer is wrong. Even working backwords from .45points i get .75 gyr

(2)Hydraulic engineers often use, as a unit of volume of water, the "acre-foot", defined as the volume of water that will cover 1 acre of land to a depth of 1 ft. A severe thunderstorm dumps 1.7 in. of rain in 30 min on a town of area 36 km2. What volume of water, in acre-feet, fell on the town?|

I calculated the volume of water to be 16732.28346ft^3. After i divided that number by 43560ft^3 and my answer was 0.3841203733 acre-ft

(3)Gold, which has a mass of 19.32 g for each cubic centimeter of volume, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber.

(a) If a sample of gold, with a mass of 77.36 g, is pressed into a leaf of 2.800 µm thickness, what is the area of the leaf?b) If, instead, the gold is drawn out into a cylindrical fiber of radius 2.000 µm, what is the length of the fiber?

The volume in cm^3 would be (77.36/19.32)/100= V I calculated the 2.8 micron thickness to be 0.00028m. After that i divded the volume by the thickness to get the area(pretty sure they dont want surface area) to get A=143.005m^2

For B, using the same volume i divided the area (pi(2x10^-6)^2) to get the length of 3186393995m

A cubic centimeter in a typical cumulus cloud contains 50 to 500 water drops, which have a typical radius of 10 µm. For that range, give the lower value and the higher value, respectively, for the following.

(a) How many cubic meters of water are in a cylindrical cumulus cloud of height 2.0 km and radius 1.0 km?

to m3

(b) How many 1 liter pop bottles would that water fill?

to bottles

(c) Water has a mass per unit volume (or density) of 1000 kg/m3. How much mass does the water in the cloud have?

I had to assume they wanted me to use the radius of the water drop to caluclate the volume of one drop as a sphere then multiply it by the number of drops (50 and/or 500) and then by the number of cubic centimeters in the cloud. Again my answer was wrong

Any insight into what i am doing wrong on these would be greatly appreciated.