One half, three quarters, one eighth, one sixteenth and eleven 30 minutes to find the rules`````

One half, three quarters, one eighth, one sixteenth and eleven 30 minutes to find the rules`````

The denominator is to the power of 2
The molecule is the previous number multiplied by 3
1/2 3/4 9/8 27/16 81/32 243/64

Known chord length 6.5m, arch height 0.6m, find arc length? (please give detailed calculation formula) urgent!

Given chord length L = 6.5m, arch height h = 0.6m, calculate arc length C?
The radius of arc is r, and the center angle of arc is a
R^2=(R-H)^2+(L/2)^2
R^2=R^2-2*R*H+H^2+L^2/4
2*R*H=H^2+L^2/4
R=H/2+L^2/(8*H)
=0.6/2+6.5^2/(8*0.6)
=9.102m
A=2*ARC SIN((L/2)/R)
=2*ARC SIN((6.5/2)/9.102)
=41.84 degrees
=41.84*PI/180
=73024 radians
C=A*R
=0.73024*9.102
=647m

If the sum of the first three terms of an arithmetic sequence is 34, the sum of the last three terms is 146, and the sum of all terms is 390, then the sequence has ()
A. 13 items B. 12 items C. 11 items D. 10 items

According to the meaning of the title, a1 + A2 + a3 = 34, an + an-1 + An-2 = 146 〈 a1 + A2 + a3 + an + an-1 + An-2 = 34 + 146 = 180 and ∵ a1 + an = A2 + an-1 = A3 + An-2 〉 a1 + an = 1803 = 60 〉 SN = (a1 + an) & nbsp; N2 = 60n2 = 390 〉 n = 13, so a is chosen

The number 3 less than 2 / 5 of X is 16 and 1 / 5 to solve X series equation

16 and 1 / 5 = 81 / 5
2x/5-3=81/5
2x/5=96/5
x=96/5*5/2
x=48

Ten English compositions in grade one, about 50 words, fast

My net friend I was only nine years old when I learned how to use a computer. My mother is my first teacher. I know how to type, how to copy a file, and how to visit a web site on the Internet

The ratio of 1 / 2:0.75 to the simplest integer is, the ratio is

The ratio of 1 / 2:0.75 to the simplest integer is 2:3, and the ratio is 2 / 3

How to solve equation 2 (x + 1) = 63

2x+2=63
2x=61
x=30.5

There is a cuboid with a surface area of 184 square centimeters, a bottom area of 20 square centimeters, and a bottom perimeter of 18 centimeters. The cuboid has a volume of______ Cubic centimeter

20 × [(184-20 × 2) △ 18], = 20 × [(184-40) △ 18], = 20 × [144 △ 18], = 20 × 8, = 160 (cubic centimeter). Answer: the volume of this cuboid is 160 cubic centimeter. So the answer is: 160

Given that the point P (Tana, COSA) is in the third quadrant, then which quadrant is the edge of angle a,

2

32 (1-x) 2 = 18,

(32-32X)*2=18
64-64X=18
64-18=64X
48=64X
X=48/64
X=3/4