Answer:
I think that the answer is 2.5 , the second item .
You have to know what it is before you solve the problem
V = 1/3 • π • radius cubed • height
If the volume is is 16π and the height is 3, then 16π = 1/3 • π • r cubed • 3
16π ÷ (1/3 • π • 3) = 16
radius squared = 16 √16 = 4, so radius = 4
You can also check: 1/3 • r cubed • 3 = 16 The only value left to multiply is π
Answer:
24.997 = 25.00 (rounded off to 2 decimal figures)
Step-by-step explanation:
By observation, we can see that both straight lines are of equal length and that the angle between the lines is 90°. Hence we can conclude that this is a quadrant of a circle with radius, r = 7 cm.
length of the curved section
= 1/4 x circumference of the circle
= 1/4 x 2πr
= 1/4 x 2 x 3.142 x 7
= 10.997 cm²
HEnce circumference = 10.997 + 7 + 7 = 24.997 = 25.00 (rounded off to 2 decimal figures)