Step-by-step explanation:
b is per the identity of angles on parallel lines when intersected by one inclined line the same as the 40° angle.
so,
b = 40°
due to the parallel nature of the 2 lines there is a symmetry effect for such shapes inscribed a circle. the upper and the lower triangle must be similar. and when applying a vertical line through the central crossing point, everything to the left is mirrored by everything on the right.
so, angle c must be equal to angle b.
c = 40°
and as the sum of all angles in a triangle is always 180°, d is then
d = 180 - 40 - 40 = 100°
the interior angle of the arc angle a is the supplementary angle of d (together they are 180°), because together with d they cover the full down side of the top-left to bottom-right line.
interior angle to a = 180 - 100 = 80°
due to the symmetry again, the arc angle opposite to a is the same as a.
as we know, the interior angle to a pair of opposing arc angles is the mean value of the 2 angles.
so, we have
(a + a)/2 = 80
2a/2 = 80
a = 80°
there might (and actually should) be some more direct approaches for "a" out of the other pieces of information, but that was the most straight one right out of my mind, and I don't spend time on finding additional shortcuts, when I have already a working approach.
When an spherical balloon volume is increasing at the rate of
then the diameter of the balloon is increasing 
How can we find the rate of change of balloon's diameter ?
The volume of a spherical balloon is 
In form of diameter we can write as

Now we will differentiate both sides wrt to
we get

Given in the question 
thus when we substitute the values we get

Learn more about the differentiation here:
brainly.com/question/28046488
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Answer:
7
Step-by-step explanation:
21/3
3 will council it self one and 21 7times
Answer:
The curvature is 
The tangential component of acceleration is 
The normal component of acceleration is 
Step-by-step explanation:
To find the curvature of the path we are going to use this formula:

where
is the unit tangent vector.
is the speed of the object
We need to find
, we know that
so

Next , we find the magnitude of derivative of the position vector

The unit tangent vector is defined by


We need to find the derivative of unit tangent vector

And the magnitude of the derivative of unit tangent vector is

The curvature is

The tangential component of acceleration is given by the formula

We know that
and 
so

The normal component of acceleration is given by the formula

We know that
and
so
