22.6is the answer check it first .
The formula of cicumfrance is
C= 2 x pi x r
2b 2a
----------------- + -----------------
(b+a)^2 (b^2 - a^2)
2b 2a
= ----------------- + -------------------
(b+a)(b+a) (b+a)(b-a)
2b(b - a) + 2a(b + a)
= ------------------------------------
(b+a)(b+a)(b-a)
2b^2 - 2ab + 2ab + 2a^2
= ---------------------------------------
(b+a)(b+a)(b-a)
2b^2 + 2a^2
= ------------------------
(b+a)(b+a)(b-a)
2(b^2 + a^2)
= ------------------------
(b+a)^2 (b-a)
Answer:
Numerator: 2(b^2 + a^2)
Denominator: (b+a)^2 (b-a)
For the second one 1 mph equals 1.6 km so i’m pretty sure it would be all of them
Answer:

8,3*0,25=2,10%(2d.p)
Step-by-step explanation:
Answer:
13 seashells
Step-by-step explanation:
p=number of seashells pierre collected
p+3p=52
4p=52
p=13
13 seashells