Answer:
Step-by-step explanation:
All the interior angles are of measure 60 degrees.
We want to find the height of this triangle. Call it h. On the left side of this illustration is a right triangle with height h and base (1/2)(10), or 5.
The ratio of height to base is the tangent of 60 degrees:
h
tan 60 degrees = --------------
5
h
and tan 60 degrees = 1.73 = ------
5
Multiplying both sides of this equation by 5 yields h = 8.66. This is |BD|. This is the same as Answer B.

As we know :
Dividend = Divisor × Quotient ( taking remainder as 0 )
So, Quotient = Dividend ÷ Divisor
by using the above relation we can say :
therefore, correct option is C. t ÷ 23
9) 0.31
10) (7x10^6)-(3x10^3)
7000000-3000=6997000
6.997x10^6
Hope this helps :)