Answer:
Step-by-step explanation:
Garden roller is in the shape of cylinder.
So, one revolution = Curved surface area of the cylinder
diameter = 70 cm
radius = 70/2 = 35 cm
h = 100 cm
Curved surface area of the cylinder = 2πrh
=
= 22000 square cm
Area covered in 15 revolutions = 15 * 22000
= 330000 square cm
2) Coin
diameter = 22 mm
r = 22/2 = 11 mm
Volume of coin = 66 mm
πr²h = 66
Answer:
Option A
Step-by-step explanation:
From the question given in the picture attached,
Directrix of the parabola → y = 2
Focus of the parabola → (-5, 0)
Since, focus is below the directrix, parabola will open open downwards.
Equation of the parabola will be in the form of,
y - k = -4p(x - h)²
Here, (h, k) is the vertex of the parabola
p = Distance between vertex and focus or distance between vertex and directrix
Since, distance between vertex and focus = Distance between vertex and directrix
Therefore, vertex of the parabola → (-5, 1)
Now distance (p) between vertex (-5, 0) and focus (-5, 1) = 1 unit
By substituting these values in the equation,
y - 1 = -4(1)[x - (-5)]²
y - 1 = -4(x + 5)²
y = -4(x + 5)² + 1
Option A will be the answer.
