3/20 is the same as 15/100 or 15%
so 10×3/20 would be the same as 10×15% or 150%
Is that what you were asking?
1st :The angle of depression 30° = the angle of elevation (from the truck to the height of the building.
2nd :
cos 30° = (adjacent side)/(hypotenuse)
cos 30° = x/100, but cos 30°= (√3)/2
(√3)/2 = x/100 and x = (100√3)/2
and x = (50.√3) = 86.60 m
Answer:

Step-by-step explanation:
Tan can be defined as:
as it simplifies to opposite/adjacent. If you know a bit about the unit circle, you'll know that the x-coordinate is going to be cos(theta) and the y-coordinate is going to be sin(theta). Since the sin(theta) is defined as opposite/hypotenuse, and the hypotenuse = 1, so sin(theta) is defined as the opposite side, which is the y-axis. Same thing goes for cos(theta), except the adjacent side is the x-axis.
Using this we can define tan

Answer:
The approximate volume of the tank is 
Step-by-step explanation:
we know that
The volume of a hemisphere (water storage tank) is equal to

we have

assume

substitute

