Step-by-step explanation:
It is given that,
The diameter of a tennis ball is 2 cm and the diameter of the softball is 1 cm. So, radius of tennis ball is 1 cm and radius of softball is 0.5 cm.
Both balls are in the shape of sphere. Half of the balls will becomes hemisphere. The surface area of hemisphere is given by :

Taking ratio of both balls, i.e.


So, the surface area of a half of the tennis ball is 4 times of he surface area of a half of the softball.
Q28 the sum of odd numbers n will be
Sum=n*n
Sum off odd number 100
Sum=100*100=10000
This is the formula of finding the hypotenuse: a² + b² = c².
So the legs would be a and b.
4² + 4² = c²
c² = 16 + 16
c² = 32
c = √32 (Option C)
P=s1+s2+s3
Move +s1 to the other side. Sign changes from +s1 to -s1
P-s1=s1-s1+s2+s3
p-s1=s2+s3
Move s2 to the other side. Sign changes from s2 to -s2
p-s1-s2=s2-s2+s3
p-s1-s2=s3
Answer: p-s1-s2=s3