Questions

The head mirror used by ENT doctors is concave.

Let the missing numbers be x, y, a and b

x + y = 8 ---- (1)
a - b = 6 ---- (2)
x + a = 13 --- (3)
y + b = 8 ---- (4)

2x + a + y = 21 --- From (1 & 3)
a + y = 14 ----  From (2 & 4)

Substitute (2 & 4) in (1 & 3)

2x + 14 = 21
2x = 7
x = 3.5

From (1) ---> 3.5 + y = 8
=> y = 8 - 3.5 = 4.5

a + y = 14 => a = 14 - y = 14 - 4.5 => a = 9.5
From (4) ---- y + b = 8 => b = 8 - y = 8 - 4.5 = 3.5

Hence,
x = 3.5
y = 4.5
a = 9.5
b = 3.5

A mountain is what has roots that nobody sees, Is taller than trees, Up, up it goes, Yet it never grows.

The Cartesian Coordinates can be retrieved from spherical coordinates (l,q,a) by:

X = r.sinq.cosa

Y = r.sinq.sina

Z = r.sinq

Using the same we get for P,

Y = P.sinq.sina

Ctrl + F is a shorcut keyword and it is used for searching the word you want in the large document in the M.S. Word.