Answer:
54.5 
Step-by-step explanation:
divide it to one rectangle and two different triangles.
Rectangles area: (8+3)*4 = 44
triangle top: 4*3/2 = 6
triangle bottom: 3*3/2= 4.5
sum the all up: 44+6+4.5 = 54.5
don't know how to do it with π though if that's obligatory
true because the square root is a number times itself and 4*4 is 16
6hrs = 360 minutes
360/7.5 = 48 bottles required
500g = 0.5kg
48x0.5 = 24 kg
24x 5 = 120p
40% percent times 70 is want I believe